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#41
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CD Quality Difference in Player
Please read my post again.
I said that AGC is a threshold detector function. It has nothing to do with laser diode power calibration. Sony players do nothing special with the laser diode. The AGC function provides variable threshold detection, which is what gives it the ability to read Orange Book. "Mark D. Zacharias" wrote in message ... And yet the laser power is not calibrated according to any disc reflectivity, merely to provide a constant laser current, which is virtually the same regardless of whether any laser light returns from the disc at all. In a multi-read model, which I will admit I have not studied, this may be different. Your old Sony however, isn't multi-read in the same sense as a modern CD-ROM device. It may just have the laser power turned up somewhat. The only unit I have seen which calibrated the laser output on playback was a karaoke model - unknown Chinese vendor. Viewing the HF pattern on a 'scope one could observe the laser "eye pattern" ramping up depending on the disc type. Your Sony does not do this. Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... "Mark D. Zacharias" wrote in message ... I was talking CD-R, not RW, haven't tried those in the older Sony's but I would be surprised. Lots of other units use the Sony pickups, and none of them boost the laser power based on reflectivity - a constant current is maintained as a voltage drop across a resistor, indicating a constant laser diode current, regardless of reflected signal received back to the diode pack. The APC (not ACG) transistor is mainly a switch, though as I say the current is kept nearly constant. Mark Z. I did not intend to imply that AGC is an adjustment of the laser diode. It is an adjustment of the threshold detector. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... Sorry, Mark, I can't agree. The following tech sheet http://www.sanyo.com/semiconductors/news/Vol66.pdf gives specs on the Sayn LA9251M, a common CD controller chip. Among the features provided is . Automatic follower operation (tracking gain and track detection level) Because lasers wear and output decays over time, calibration to the reflected signal at a particular point in the life in the product is essential. This feature is frequently referred to as AGC, and has been implemented with varying degrees of effectivenss in different players. For example, every Sony player I own, back to 1991, is multi-read capable, which means that it can read a CD-RW, which of all the available blanks differs the greatest from a pressing. Most other brands were, at least in the past, not nearly so good. It is remarkable that Sony built multi-read into their products long before CD-RW was in frequent use. I have the service manual for all my players, and none of these older, multiread capable units have either a calibration pot or a service mode. "Mark D. Zacharias" wrote in message ... With VERY few exceptions, audio CD players do not calibrate laser power automatically. Some are adjusted with physical potentiometers, some newer ones do it in a service mode using eeproms, but once set, the laser calibration is done. Focus is adjusted dynamically while playing, and of course during the focus search routine. Focus offset value is kept in memory until the next disc read operation so that if the PLAY button is pressed again, it can spin immediately without doing another focus search. Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... "Surinder Singh" wrote in message ... I play the CD's I burn in Phillipps Boombox. If I Maxell Gold CD-R it takes 20 seconds for the boom box to recognize the tracks and be ready to play it after inserting the CD. With Memorex 52x, it takes only 2 seconds for boom to recognize the tracks. Does it mean that Memorex is better quality? I would have thought the gold coloration ;-) & Maxell name would make the former a better quality? Thanks. Different CD disks have different reflectivities for the burn/no burn conditions. The CD player has a calibration function that enables it to correctly recognize these conditions. Depending upon the design of the player, the ability to recognize disks with different reflectivities vary. Only a few years ago, it was common for many brands of CD players to fail to recognize CD-Rs, because insufficient range had been built into the calibration function. What you observe has more to do with the player than the disk. Gold as a reflective material has a signficant advantage for archival use. However, it is somewhat less reflective than aluminum. |
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#42
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CD Quality Difference in Player
I think we're at cross purposes. Red Book doesn't define CD-RW as opposed to
CD-R, does it? Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... Please read my post again. I said that AGC is a threshold detector function. It has nothing to do with laser diode power calibration. Sony players do nothing special with the laser diode. The AGC function provides variable threshold detection, which is what gives it the ability to read Orange Book. "Mark D. Zacharias" wrote in message ... And yet the laser power is not calibrated according to any disc reflectivity, merely to provide a constant laser current, which is virtually the same regardless of whether any laser light returns from the disc at all. In a multi-read model, which I will admit I have not studied, this may be different. Your old Sony however, isn't multi-read in the same sense as a modern CD-ROM device. It may just have the laser power turned up somewhat. The only unit I have seen which calibrated the laser output on playback was a karaoke model - unknown Chinese vendor. Viewing the HF pattern on a 'scope one could observe the laser "eye pattern" ramping up depending on the disc type. Your Sony does not do this. Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... "Mark D. Zacharias" wrote in message ... I was talking CD-R, not RW, haven't tried those in the older Sony's but I would be surprised. Lots of other units use the Sony pickups, and none of them boost the laser power based on reflectivity - a constant current is maintained as a voltage drop across a resistor, indicating a constant laser diode current, regardless of reflected signal received back to the diode pack. The APC (not ACG) transistor is mainly a switch, though as I say the current is kept nearly constant. Mark Z. I did not intend to imply that AGC is an adjustment of the laser diode. It is an adjustment of the threshold detector. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... Sorry, Mark, I can't agree. The following tech sheet http://www.sanyo.com/semiconductors/news/Vol66.pdf gives specs on the Sayn LA9251M, a common CD controller chip. Among the features provided is . Automatic follower operation (tracking gain and track detection level) Because lasers wear and output decays over time, calibration to the reflected signal at a particular point in the life in the product is essential. This feature is frequently referred to as AGC, and has been implemented with varying degrees of effectivenss in different players. For example, every Sony player I own, back to 1991, is multi-read capable, which means that it can read a CD-RW, which of all the available blanks differs the greatest from a pressing. Most other brands were, at least in the past, not nearly so good. It is remarkable that Sony built multi-read into their products long before CD-RW was in frequent use. I have the service manual for all my players, and none of these older, multiread capable units have either a calibration pot or a service mode. "Mark D. Zacharias" wrote in message ... With VERY few exceptions, audio CD players do not calibrate laser power automatically. Some are adjusted with physical potentiometers, some newer ones do it in a service mode using eeproms, but once set, the laser calibration is done. Focus is adjusted dynamically while playing, and of course during the focus search routine. Focus offset value is kept in memory until the next disc read operation so that if the PLAY button is pressed again, it can spin immediately without doing another focus search. Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... "Surinder Singh" wrote in message ... I play the CD's I burn in Phillipps Boombox. If I Maxell Gold CD-R it takes 20 seconds for the boom box to recognize the tracks and be ready to play it after inserting the CD. With Memorex 52x, it takes only 2 seconds for boom to recognize the tracks. Does it mean that Memorex is better quality? I would have thought the gold coloration ;-) & Maxell name would make the former a better quality? Thanks. Different CD disks have different reflectivities for the burn/no burn conditions. The CD player has a calibration function that enables it to correctly recognize these conditions. Depending upon the design of the player, the ability to recognize disks with different reflectivities vary. Only a few years ago, it was common for many brands of CD players to fail to recognize CD-Rs, because insufficient range had been built into the calibration function. What you observe has more to do with the player than the disk. Gold as a reflective material has a signficant advantage for archival use. However, it is somewhat less reflective than aluminum. |
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#43
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CD Quality Difference in Player
I think we're at cross purposes. Red Book doesn't define CD-RW as opposed to
CD-R, does it? Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... Please read my post again. I said that AGC is a threshold detector function. It has nothing to do with laser diode power calibration. Sony players do nothing special with the laser diode. The AGC function provides variable threshold detection, which is what gives it the ability to read Orange Book. "Mark D. Zacharias" wrote in message ... And yet the laser power is not calibrated according to any disc reflectivity, merely to provide a constant laser current, which is virtually the same regardless of whether any laser light returns from the disc at all. In a multi-read model, which I will admit I have not studied, this may be different. Your old Sony however, isn't multi-read in the same sense as a modern CD-ROM device. It may just have the laser power turned up somewhat. The only unit I have seen which calibrated the laser output on playback was a karaoke model - unknown Chinese vendor. Viewing the HF pattern on a 'scope one could observe the laser "eye pattern" ramping up depending on the disc type. Your Sony does not do this. Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... "Mark D. Zacharias" wrote in message ... I was talking CD-R, not RW, haven't tried those in the older Sony's but I would be surprised. Lots of other units use the Sony pickups, and none of them boost the laser power based on reflectivity - a constant current is maintained as a voltage drop across a resistor, indicating a constant laser diode current, regardless of reflected signal received back to the diode pack. The APC (not ACG) transistor is mainly a switch, though as I say the current is kept nearly constant. Mark Z. I did not intend to imply that AGC is an adjustment of the laser diode. It is an adjustment of the threshold detector. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... Sorry, Mark, I can't agree. The following tech sheet http://www.sanyo.com/semiconductors/news/Vol66.pdf gives specs on the Sayn LA9251M, a common CD controller chip. Among the features provided is . Automatic follower operation (tracking gain and track detection level) Because lasers wear and output decays over time, calibration to the reflected signal at a particular point in the life in the product is essential. This feature is frequently referred to as AGC, and has been implemented with varying degrees of effectivenss in different players. For example, every Sony player I own, back to 1991, is multi-read capable, which means that it can read a CD-RW, which of all the available blanks differs the greatest from a pressing. Most other brands were, at least in the past, not nearly so good. It is remarkable that Sony built multi-read into their products long before CD-RW was in frequent use. I have the service manual for all my players, and none of these older, multiread capable units have either a calibration pot or a service mode. "Mark D. Zacharias" wrote in message ... With VERY few exceptions, audio CD players do not calibrate laser power automatically. Some are adjusted with physical potentiometers, some newer ones do it in a service mode using eeproms, but once set, the laser calibration is done. Focus is adjusted dynamically while playing, and of course during the focus search routine. Focus offset value is kept in memory until the next disc read operation so that if the PLAY button is pressed again, it can spin immediately without doing another focus search. Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... "Surinder Singh" wrote in message ... I play the CD's I burn in Phillipps Boombox. If I Maxell Gold CD-R it takes 20 seconds for the boom box to recognize the tracks and be ready to play it after inserting the CD. With Memorex 52x, it takes only 2 seconds for boom to recognize the tracks. Does it mean that Memorex is better quality? I would have thought the gold coloration ;-) & Maxell name would make the former a better quality? Thanks. Different CD disks have different reflectivities for the burn/no burn conditions. The CD player has a calibration function that enables it to correctly recognize these conditions. Depending upon the design of the player, the ability to recognize disks with different reflectivities vary. Only a few years ago, it was common for many brands of CD players to fail to recognize CD-Rs, because insufficient range had been built into the calibration function. What you observe has more to do with the player than the disk. Gold as a reflective material has a signficant advantage for archival use. However, it is somewhat less reflective than aluminum. |
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#44
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CD Quality Difference in Player
I think we're at cross purposes. Red Book doesn't define CD-RW as opposed to
CD-R, does it? Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... Please read my post again. I said that AGC is a threshold detector function. It has nothing to do with laser diode power calibration. Sony players do nothing special with the laser diode. The AGC function provides variable threshold detection, which is what gives it the ability to read Orange Book. "Mark D. Zacharias" wrote in message ... And yet the laser power is not calibrated according to any disc reflectivity, merely to provide a constant laser current, which is virtually the same regardless of whether any laser light returns from the disc at all. In a multi-read model, which I will admit I have not studied, this may be different. Your old Sony however, isn't multi-read in the same sense as a modern CD-ROM device. It may just have the laser power turned up somewhat. The only unit I have seen which calibrated the laser output on playback was a karaoke model - unknown Chinese vendor. Viewing the HF pattern on a 'scope one could observe the laser "eye pattern" ramping up depending on the disc type. Your Sony does not do this. Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... "Mark D. Zacharias" wrote in message ... I was talking CD-R, not RW, haven't tried those in the older Sony's but I would be surprised. Lots of other units use the Sony pickups, and none of them boost the laser power based on reflectivity - a constant current is maintained as a voltage drop across a resistor, indicating a constant laser diode current, regardless of reflected signal received back to the diode pack. The APC (not ACG) transistor is mainly a switch, though as I say the current is kept nearly constant. Mark Z. I did not intend to imply that AGC is an adjustment of the laser diode. It is an adjustment of the threshold detector. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... Sorry, Mark, I can't agree. The following tech sheet http://www.sanyo.com/semiconductors/news/Vol66.pdf gives specs on the Sayn LA9251M, a common CD controller chip. Among the features provided is . Automatic follower operation (tracking gain and track detection level) Because lasers wear and output decays over time, calibration to the reflected signal at a particular point in the life in the product is essential. This feature is frequently referred to as AGC, and has been implemented with varying degrees of effectivenss in different players. For example, every Sony player I own, back to 1991, is multi-read capable, which means that it can read a CD-RW, which of all the available blanks differs the greatest from a pressing. Most other brands were, at least in the past, not nearly so good. It is remarkable that Sony built multi-read into their products long before CD-RW was in frequent use. I have the service manual for all my players, and none of these older, multiread capable units have either a calibration pot or a service mode. "Mark D. Zacharias" wrote in message ... With VERY few exceptions, audio CD players do not calibrate laser power automatically. Some are adjusted with physical potentiometers, some newer ones do it in a service mode using eeproms, but once set, the laser calibration is done. Focus is adjusted dynamically while playing, and of course during the focus search routine. Focus offset value is kept in memory until the next disc read operation so that if the PLAY button is pressed again, it can spin immediately without doing another focus search. Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... "Surinder Singh" wrote in message ... I play the CD's I burn in Phillipps Boombox. If I Maxell Gold CD-R it takes 20 seconds for the boom box to recognize the tracks and be ready to play it after inserting the CD. With Memorex 52x, it takes only 2 seconds for boom to recognize the tracks. Does it mean that Memorex is better quality? I would have thought the gold coloration ;-) & Maxell name would make the former a better quality? Thanks. Different CD disks have different reflectivities for the burn/no burn conditions. The CD player has a calibration function that enables it to correctly recognize these conditions. Depending upon the design of the player, the ability to recognize disks with different reflectivities vary. Only a few years ago, it was common for many brands of CD players to fail to recognize CD-Rs, because insufficient range had been built into the calibration function. What you observe has more to do with the player than the disk. Gold as a reflective material has a signficant advantage for archival use. However, it is somewhat less reflective than aluminum. |
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#45
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CD Quality Difference in Player
I think we're at cross purposes. Red Book doesn't define CD-RW as opposed to
CD-R, does it? Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... Please read my post again. I said that AGC is a threshold detector function. It has nothing to do with laser diode power calibration. Sony players do nothing special with the laser diode. The AGC function provides variable threshold detection, which is what gives it the ability to read Orange Book. "Mark D. Zacharias" wrote in message ... And yet the laser power is not calibrated according to any disc reflectivity, merely to provide a constant laser current, which is virtually the same regardless of whether any laser light returns from the disc at all. In a multi-read model, which I will admit I have not studied, this may be different. Your old Sony however, isn't multi-read in the same sense as a modern CD-ROM device. It may just have the laser power turned up somewhat. The only unit I have seen which calibrated the laser output on playback was a karaoke model - unknown Chinese vendor. Viewing the HF pattern on a 'scope one could observe the laser "eye pattern" ramping up depending on the disc type. Your Sony does not do this. Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... "Mark D. Zacharias" wrote in message ... I was talking CD-R, not RW, haven't tried those in the older Sony's but I would be surprised. Lots of other units use the Sony pickups, and none of them boost the laser power based on reflectivity - a constant current is maintained as a voltage drop across a resistor, indicating a constant laser diode current, regardless of reflected signal received back to the diode pack. The APC (not ACG) transistor is mainly a switch, though as I say the current is kept nearly constant. Mark Z. I did not intend to imply that AGC is an adjustment of the laser diode. It is an adjustment of the threshold detector. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... Sorry, Mark, I can't agree. The following tech sheet http://www.sanyo.com/semiconductors/news/Vol66.pdf gives specs on the Sayn LA9251M, a common CD controller chip. Among the features provided is . Automatic follower operation (tracking gain and track detection level) Because lasers wear and output decays over time, calibration to the reflected signal at a particular point in the life in the product is essential. This feature is frequently referred to as AGC, and has been implemented with varying degrees of effectivenss in different players. For example, every Sony player I own, back to 1991, is multi-read capable, which means that it can read a CD-RW, which of all the available blanks differs the greatest from a pressing. Most other brands were, at least in the past, not nearly so good. It is remarkable that Sony built multi-read into their products long before CD-RW was in frequent use. I have the service manual for all my players, and none of these older, multiread capable units have either a calibration pot or a service mode. "Mark D. Zacharias" wrote in message ... With VERY few exceptions, audio CD players do not calibrate laser power automatically. Some are adjusted with physical potentiometers, some newer ones do it in a service mode using eeproms, but once set, the laser calibration is done. Focus is adjusted dynamically while playing, and of course during the focus search routine. Focus offset value is kept in memory until the next disc read operation so that if the PLAY button is pressed again, it can spin immediately without doing another focus search. Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... "Surinder Singh" wrote in message ... I play the CD's I burn in Phillipps Boombox. If I Maxell Gold CD-R it takes 20 seconds for the boom box to recognize the tracks and be ready to play it after inserting the CD. With Memorex 52x, it takes only 2 seconds for boom to recognize the tracks. Does it mean that Memorex is better quality? I would have thought the gold coloration ;-) & Maxell name would make the former a better quality? Thanks. Different CD disks have different reflectivities for the burn/no burn conditions. The CD player has a calibration function that enables it to correctly recognize these conditions. Depending upon the design of the player, the ability to recognize disks with different reflectivities vary. Only a few years ago, it was common for many brands of CD players to fail to recognize CD-Rs, because insufficient range had been built into the calibration function. What you observe has more to do with the player than the disk. Gold as a reflective material has a signficant advantage for archival use. However, it is somewhat less reflective than aluminum. |
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#46
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CD Quality Difference in Player
I believe CD-RW is Orange Book.
"Mark D. Zacharias" wrote in message ... I think we're at cross purposes. Red Book doesn't define CD-RW as opposed to CD-R, does it? Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... Please read my post again. I said that AGC is a threshold detector function. It has nothing to do with laser diode power calibration. Sony players do nothing special with the laser diode. The AGC function provides variable threshold detection, which is what gives it the ability to read Orange Book. "Mark D. Zacharias" wrote in message ... And yet the laser power is not calibrated according to any disc reflectivity, merely to provide a constant laser current, which is virtually the same regardless of whether any laser light returns from the disc at all. In a multi-read model, which I will admit I have not studied, this may be different. Your old Sony however, isn't multi-read in the same sense as a modern CD-ROM device. It may just have the laser power turned up somewhat. The only unit I have seen which calibrated the laser output on playback was a karaoke model - unknown Chinese vendor. Viewing the HF pattern on a 'scope one could observe the laser "eye pattern" ramping up depending on the disc type. Your Sony does not do this. Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... "Mark D. Zacharias" wrote in message ... I was talking CD-R, not RW, haven't tried those in the older Sony's but I would be surprised. Lots of other units use the Sony pickups, and none of them boost the laser power based on reflectivity - a constant current is maintained as a voltage drop across a resistor, indicating a constant laser diode current, regardless of reflected signal received back to the diode pack. The APC (not ACG) transistor is mainly a switch, though as I say the current is kept nearly constant. Mark Z. I did not intend to imply that AGC is an adjustment of the laser diode. It is an adjustment of the threshold detector. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... Sorry, Mark, I can't agree. The following tech sheet http://www.sanyo.com/semiconductors/news/Vol66.pdf gives specs on the Sayn LA9251M, a common CD controller chip. Among the features provided is . Automatic follower operation (tracking gain and track detection level) Because lasers wear and output decays over time, calibration to the reflected signal at a particular point in the life in the product is essential. This feature is frequently referred to as AGC, and has been implemented with varying degrees of effectivenss in different players. For example, every Sony player I own, back to 1991, is multi-read capable, which means that it can read a CD-RW, which of all the available blanks differs the greatest from a pressing. Most other brands were, at least in the past, not nearly so good. It is remarkable that Sony built multi-read into their products long before CD-RW was in frequent use. I have the service manual for all my players, and none of these older, multiread capable units have either a calibration pot or a service mode. "Mark D. Zacharias" wrote in message ... With VERY few exceptions, audio CD players do not calibrate laser power automatically. Some are adjusted with physical potentiometers, some newer ones do it in a service mode using eeproms, but once set, the laser calibration is done. Focus is adjusted dynamically while playing, and of course during the focus search routine. Focus offset value is kept in memory until the next disc read operation so that if the PLAY button is pressed again, it can spin immediately without doing another focus search. Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... "Surinder Singh" wrote in message ... I play the CD's I burn in Phillipps Boombox. If I Maxell Gold CD-R it takes 20 seconds for the boom box to recognize the tracks and be ready to play it after inserting the CD. With Memorex 52x, it takes only 2 seconds for boom to recognize the tracks. Does it mean that Memorex is better quality? I would have thought the gold coloration ;-) & Maxell name would make the former a better quality? Thanks. Different CD disks have different reflectivities for the burn/no burn conditions. The CD player has a calibration function that enables it to correctly recognize these conditions. Depending upon the design of the player, the ability to recognize disks with different reflectivities vary. Only a few years ago, it was common for many brands of CD players to fail to recognize CD-Rs, because insufficient range had been built into the calibration function. What you observe has more to do with the player than the disk. Gold as a reflective material has a signficant advantage for archival use. However, it is somewhat less reflective than aluminum. |
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#47
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CD Quality Difference in Player
I believe CD-RW is Orange Book.
"Mark D. Zacharias" wrote in message ... I think we're at cross purposes. Red Book doesn't define CD-RW as opposed to CD-R, does it? Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... Please read my post again. I said that AGC is a threshold detector function. It has nothing to do with laser diode power calibration. Sony players do nothing special with the laser diode. The AGC function provides variable threshold detection, which is what gives it the ability to read Orange Book. "Mark D. Zacharias" wrote in message ... And yet the laser power is not calibrated according to any disc reflectivity, merely to provide a constant laser current, which is virtually the same regardless of whether any laser light returns from the disc at all. In a multi-read model, which I will admit I have not studied, this may be different. Your old Sony however, isn't multi-read in the same sense as a modern CD-ROM device. It may just have the laser power turned up somewhat. The only unit I have seen which calibrated the laser output on playback was a karaoke model - unknown Chinese vendor. Viewing the HF pattern on a 'scope one could observe the laser "eye pattern" ramping up depending on the disc type. Your Sony does not do this. Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... "Mark D. Zacharias" wrote in message ... I was talking CD-R, not RW, haven't tried those in the older Sony's but I would be surprised. Lots of other units use the Sony pickups, and none of them boost the laser power based on reflectivity - a constant current is maintained as a voltage drop across a resistor, indicating a constant laser diode current, regardless of reflected signal received back to the diode pack. The APC (not ACG) transistor is mainly a switch, though as I say the current is kept nearly constant. Mark Z. I did not intend to imply that AGC is an adjustment of the laser diode. It is an adjustment of the threshold detector. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... Sorry, Mark, I can't agree. The following tech sheet http://www.sanyo.com/semiconductors/news/Vol66.pdf gives specs on the Sayn LA9251M, a common CD controller chip. Among the features provided is . Automatic follower operation (tracking gain and track detection level) Because lasers wear and output decays over time, calibration to the reflected signal at a particular point in the life in the product is essential. This feature is frequently referred to as AGC, and has been implemented with varying degrees of effectivenss in different players. For example, every Sony player I own, back to 1991, is multi-read capable, which means that it can read a CD-RW, which of all the available blanks differs the greatest from a pressing. Most other brands were, at least in the past, not nearly so good. It is remarkable that Sony built multi-read into their products long before CD-RW was in frequent use. I have the service manual for all my players, and none of these older, multiread capable units have either a calibration pot or a service mode. "Mark D. Zacharias" wrote in message ... With VERY few exceptions, audio CD players do not calibrate laser power automatically. Some are adjusted with physical potentiometers, some newer ones do it in a service mode using eeproms, but once set, the laser calibration is done. Focus is adjusted dynamically while playing, and of course during the focus search routine. Focus offset value is kept in memory until the next disc read operation so that if the PLAY button is pressed again, it can spin immediately without doing another focus search. Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... "Surinder Singh" wrote in message ... I play the CD's I burn in Phillipps Boombox. If I Maxell Gold CD-R it takes 20 seconds for the boom box to recognize the tracks and be ready to play it after inserting the CD. With Memorex 52x, it takes only 2 seconds for boom to recognize the tracks. Does it mean that Memorex is better quality? I would have thought the gold coloration ;-) & Maxell name would make the former a better quality? Thanks. Different CD disks have different reflectivities for the burn/no burn conditions. The CD player has a calibration function that enables it to correctly recognize these conditions. Depending upon the design of the player, the ability to recognize disks with different reflectivities vary. Only a few years ago, it was common for many brands of CD players to fail to recognize CD-Rs, because insufficient range had been built into the calibration function. What you observe has more to do with the player than the disk. Gold as a reflective material has a signficant advantage for archival use. However, it is somewhat less reflective than aluminum. |
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#48
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CD Quality Difference in Player
I believe CD-RW is Orange Book.
"Mark D. Zacharias" wrote in message ... I think we're at cross purposes. Red Book doesn't define CD-RW as opposed to CD-R, does it? Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... Please read my post again. I said that AGC is a threshold detector function. It has nothing to do with laser diode power calibration. Sony players do nothing special with the laser diode. The AGC function provides variable threshold detection, which is what gives it the ability to read Orange Book. "Mark D. Zacharias" wrote in message ... And yet the laser power is not calibrated according to any disc reflectivity, merely to provide a constant laser current, which is virtually the same regardless of whether any laser light returns from the disc at all. In a multi-read model, which I will admit I have not studied, this may be different. Your old Sony however, isn't multi-read in the same sense as a modern CD-ROM device. It may just have the laser power turned up somewhat. The only unit I have seen which calibrated the laser output on playback was a karaoke model - unknown Chinese vendor. Viewing the HF pattern on a 'scope one could observe the laser "eye pattern" ramping up depending on the disc type. Your Sony does not do this. Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... "Mark D. Zacharias" wrote in message ... I was talking CD-R, not RW, haven't tried those in the older Sony's but I would be surprised. Lots of other units use the Sony pickups, and none of them boost the laser power based on reflectivity - a constant current is maintained as a voltage drop across a resistor, indicating a constant laser diode current, regardless of reflected signal received back to the diode pack. The APC (not ACG) transistor is mainly a switch, though as I say the current is kept nearly constant. Mark Z. I did not intend to imply that AGC is an adjustment of the laser diode. It is an adjustment of the threshold detector. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... Sorry, Mark, I can't agree. The following tech sheet http://www.sanyo.com/semiconductors/news/Vol66.pdf gives specs on the Sayn LA9251M, a common CD controller chip. Among the features provided is . Automatic follower operation (tracking gain and track detection level) Because lasers wear and output decays over time, calibration to the reflected signal at a particular point in the life in the product is essential. This feature is frequently referred to as AGC, and has been implemented with varying degrees of effectivenss in different players. For example, every Sony player I own, back to 1991, is multi-read capable, which means that it can read a CD-RW, which of all the available blanks differs the greatest from a pressing. Most other brands were, at least in the past, not nearly so good. It is remarkable that Sony built multi-read into their products long before CD-RW was in frequent use. I have the service manual for all my players, and none of these older, multiread capable units have either a calibration pot or a service mode. "Mark D. Zacharias" wrote in message ... With VERY few exceptions, audio CD players do not calibrate laser power automatically. Some are adjusted with physical potentiometers, some newer ones do it in a service mode using eeproms, but once set, the laser calibration is done. Focus is adjusted dynamically while playing, and of course during the focus search routine. Focus offset value is kept in memory until the next disc read operation so that if the PLAY button is pressed again, it can spin immediately without doing another focus search. Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... "Surinder Singh" wrote in message ... I play the CD's I burn in Phillipps Boombox. If I Maxell Gold CD-R it takes 20 seconds for the boom box to recognize the tracks and be ready to play it after inserting the CD. With Memorex 52x, it takes only 2 seconds for boom to recognize the tracks. Does it mean that Memorex is better quality? I would have thought the gold coloration ;-) & Maxell name would make the former a better quality? Thanks. Different CD disks have different reflectivities for the burn/no burn conditions. The CD player has a calibration function that enables it to correctly recognize these conditions. Depending upon the design of the player, the ability to recognize disks with different reflectivities vary. Only a few years ago, it was common for many brands of CD players to fail to recognize CD-Rs, because insufficient range had been built into the calibration function. What you observe has more to do with the player than the disk. Gold as a reflective material has a signficant advantage for archival use. However, it is somewhat less reflective than aluminum. |
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#49
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CD Quality Difference in Player
I believe CD-RW is Orange Book.
"Mark D. Zacharias" wrote in message ... I think we're at cross purposes. Red Book doesn't define CD-RW as opposed to CD-R, does it? Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... Please read my post again. I said that AGC is a threshold detector function. It has nothing to do with laser diode power calibration. Sony players do nothing special with the laser diode. The AGC function provides variable threshold detection, which is what gives it the ability to read Orange Book. "Mark D. Zacharias" wrote in message ... And yet the laser power is not calibrated according to any disc reflectivity, merely to provide a constant laser current, which is virtually the same regardless of whether any laser light returns from the disc at all. In a multi-read model, which I will admit I have not studied, this may be different. Your old Sony however, isn't multi-read in the same sense as a modern CD-ROM device. It may just have the laser power turned up somewhat. The only unit I have seen which calibrated the laser output on playback was a karaoke model - unknown Chinese vendor. Viewing the HF pattern on a 'scope one could observe the laser "eye pattern" ramping up depending on the disc type. Your Sony does not do this. Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... "Mark D. Zacharias" wrote in message ... I was talking CD-R, not RW, haven't tried those in the older Sony's but I would be surprised. Lots of other units use the Sony pickups, and none of them boost the laser power based on reflectivity - a constant current is maintained as a voltage drop across a resistor, indicating a constant laser diode current, regardless of reflected signal received back to the diode pack. The APC (not ACG) transistor is mainly a switch, though as I say the current is kept nearly constant. Mark Z. I did not intend to imply that AGC is an adjustment of the laser diode. It is an adjustment of the threshold detector. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... Sorry, Mark, I can't agree. The following tech sheet http://www.sanyo.com/semiconductors/news/Vol66.pdf gives specs on the Sayn LA9251M, a common CD controller chip. Among the features provided is . Automatic follower operation (tracking gain and track detection level) Because lasers wear and output decays over time, calibration to the reflected signal at a particular point in the life in the product is essential. This feature is frequently referred to as AGC, and has been implemented with varying degrees of effectivenss in different players. For example, every Sony player I own, back to 1991, is multi-read capable, which means that it can read a CD-RW, which of all the available blanks differs the greatest from a pressing. Most other brands were, at least in the past, not nearly so good. It is remarkable that Sony built multi-read into their products long before CD-RW was in frequent use. I have the service manual for all my players, and none of these older, multiread capable units have either a calibration pot or a service mode. "Mark D. Zacharias" wrote in message ... With VERY few exceptions, audio CD players do not calibrate laser power automatically. Some are adjusted with physical potentiometers, some newer ones do it in a service mode using eeproms, but once set, the laser calibration is done. Focus is adjusted dynamically while playing, and of course during the focus search routine. Focus offset value is kept in memory until the next disc read operation so that if the PLAY button is pressed again, it can spin immediately without doing another focus search. Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... "Surinder Singh" wrote in message ... I play the CD's I burn in Phillipps Boombox. If I Maxell Gold CD-R it takes 20 seconds for the boom box to recognize the tracks and be ready to play it after inserting the CD. With Memorex 52x, it takes only 2 seconds for boom to recognize the tracks. Does it mean that Memorex is better quality? I would have thought the gold coloration ;-) & Maxell name would make the former a better quality? Thanks. Different CD disks have different reflectivities for the burn/no burn conditions. The CD player has a calibration function that enables it to correctly recognize these conditions. Depending upon the design of the player, the ability to recognize disks with different reflectivities vary. Only a few years ago, it was common for many brands of CD players to fail to recognize CD-Rs, because insufficient range had been built into the calibration function. What you observe has more to do with the player than the disk. Gold as a reflective material has a signficant advantage for archival use. However, it is somewhat less reflective than aluminum. |
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#50
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CD Quality Difference in Player
Well, if we're interested in continuing this mini-thread, if you don't mind,
let me just ask this, based on my recollection of an earlier post - does your old Sony read CD-RW discs, as opposed to CD-R discs? Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... I believe CD-RW is Orange Book. "Mark D. Zacharias" wrote in message ... I think we're at cross purposes. Red Book doesn't define CD-RW as opposed to CD-R, does it? Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... Please read my post again. I said that AGC is a threshold detector function. It has nothing to do with laser diode power calibration. Sony players do nothing special with the laser diode. The AGC function provides variable threshold detection, which is what gives it the ability to read Orange Book. "Mark D. Zacharias" wrote in message ... And yet the laser power is not calibrated according to any disc reflectivity, merely to provide a constant laser current, which is virtually the same regardless of whether any laser light returns from the disc at all. In a multi-read model, which I will admit I have not studied, this may be different. Your old Sony however, isn't multi-read in the same sense as a modern CD-ROM device. It may just have the laser power turned up somewhat. The only unit I have seen which calibrated the laser output on playback was a karaoke model - unknown Chinese vendor. Viewing the HF pattern on a 'scope one could observe the laser "eye pattern" ramping up depending on the disc type. Your Sony does not do this. Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... "Mark D. Zacharias" wrote in message ... I was talking CD-R, not RW, haven't tried those in the older Sony's but I would be surprised. Lots of other units use the Sony pickups, and none of them boost the laser power based on reflectivity - a constant current is maintained as a voltage drop across a resistor, indicating a constant laser diode current, regardless of reflected signal received back to the diode pack. The APC (not ACG) transistor is mainly a switch, though as I say the current is kept nearly constant. Mark Z. I did not intend to imply that AGC is an adjustment of the laser diode. It is an adjustment of the threshold detector. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... Sorry, Mark, I can't agree. The following tech sheet http://www.sanyo.com/semiconductors/news/Vol66.pdf gives specs on the Sayn LA9251M, a common CD controller chip. Among the features provided is . Automatic follower operation (tracking gain and track detection level) Because lasers wear and output decays over time, calibration to the reflected signal at a particular point in the life in the product is essential. This feature is frequently referred to as AGC, and has been implemented with varying degrees of effectivenss in different players. For example, every Sony player I own, back to 1991, is multi-read capable, which means that it can read a CD-RW, which of all the available blanks differs the greatest from a pressing. Most other brands were, at least in the past, not nearly so good. It is remarkable that Sony built multi-read into their products long before CD-RW was in frequent use. I have the service manual for all my players, and none of these older, multiread capable units have either a calibration pot or a service mode. "Mark D. Zacharias" wrote in message ... With VERY few exceptions, audio CD players do not calibrate laser power automatically. Some are adjusted with physical potentiometers, some newer ones do it in a service mode using eeproms, but once set, the laser calibration is done. Focus is adjusted dynamically while playing, and of course during the focus search routine. Focus offset value is kept in memory until the next disc read operation so that if the PLAY button is pressed again, it can spin immediately without doing another focus search. Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... "Surinder Singh" wrote in message ... I play the CD's I burn in Phillipps Boombox. If I Maxell Gold CD-R it takes 20 seconds for the boom box to recognize the tracks and be ready to play it after inserting the CD. With Memorex 52x, it takes only 2 seconds for boom to recognize the tracks. Does it mean that Memorex is better quality? I would have thought the gold coloration ;-) & Maxell name would make the former a better quality? Thanks. Different CD disks have different reflectivities for the burn/no burn conditions. The CD player has a calibration function that enables it to correctly recognize these conditions. Depending upon the design of the player, the ability to recognize disks with different reflectivities vary. Only a few years ago, it was common for many brands of CD players to fail to recognize CD-Rs, because insufficient range had been built into the calibration function. What you observe has more to do with the player than the disk. Gold as a reflective material has a signficant advantage for archival use. However, it is somewhat less reflective than aluminum. |
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#51
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CD Quality Difference in Player
Well, if we're interested in continuing this mini-thread, if you don't mind,
let me just ask this, based on my recollection of an earlier post - does your old Sony read CD-RW discs, as opposed to CD-R discs? Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... I believe CD-RW is Orange Book. "Mark D. Zacharias" wrote in message ... I think we're at cross purposes. Red Book doesn't define CD-RW as opposed to CD-R, does it? Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... Please read my post again. I said that AGC is a threshold detector function. It has nothing to do with laser diode power calibration. Sony players do nothing special with the laser diode. The AGC function provides variable threshold detection, which is what gives it the ability to read Orange Book. "Mark D. Zacharias" wrote in message ... And yet the laser power is not calibrated according to any disc reflectivity, merely to provide a constant laser current, which is virtually the same regardless of whether any laser light returns from the disc at all. In a multi-read model, which I will admit I have not studied, this may be different. Your old Sony however, isn't multi-read in the same sense as a modern CD-ROM device. It may just have the laser power turned up somewhat. The only unit I have seen which calibrated the laser output on playback was a karaoke model - unknown Chinese vendor. Viewing the HF pattern on a 'scope one could observe the laser "eye pattern" ramping up depending on the disc type. Your Sony does not do this. Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... "Mark D. Zacharias" wrote in message ... I was talking CD-R, not RW, haven't tried those in the older Sony's but I would be surprised. Lots of other units use the Sony pickups, and none of them boost the laser power based on reflectivity - a constant current is maintained as a voltage drop across a resistor, indicating a constant laser diode current, regardless of reflected signal received back to the diode pack. The APC (not ACG) transistor is mainly a switch, though as I say the current is kept nearly constant. Mark Z. I did not intend to imply that AGC is an adjustment of the laser diode. It is an adjustment of the threshold detector. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... Sorry, Mark, I can't agree. The following tech sheet http://www.sanyo.com/semiconductors/news/Vol66.pdf gives specs on the Sayn LA9251M, a common CD controller chip. Among the features provided is . Automatic follower operation (tracking gain and track detection level) Because lasers wear and output decays over time, calibration to the reflected signal at a particular point in the life in the product is essential. This feature is frequently referred to as AGC, and has been implemented with varying degrees of effectivenss in different players. For example, every Sony player I own, back to 1991, is multi-read capable, which means that it can read a CD-RW, which of all the available blanks differs the greatest from a pressing. Most other brands were, at least in the past, not nearly so good. It is remarkable that Sony built multi-read into their products long before CD-RW was in frequent use. I have the service manual for all my players, and none of these older, multiread capable units have either a calibration pot or a service mode. "Mark D. Zacharias" wrote in message ... With VERY few exceptions, audio CD players do not calibrate laser power automatically. Some are adjusted with physical potentiometers, some newer ones do it in a service mode using eeproms, but once set, the laser calibration is done. Focus is adjusted dynamically while playing, and of course during the focus search routine. Focus offset value is kept in memory until the next disc read operation so that if the PLAY button is pressed again, it can spin immediately without doing another focus search. Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... "Surinder Singh" wrote in message ... I play the CD's I burn in Phillipps Boombox. If I Maxell Gold CD-R it takes 20 seconds for the boom box to recognize the tracks and be ready to play it after inserting the CD. With Memorex 52x, it takes only 2 seconds for boom to recognize the tracks. Does it mean that Memorex is better quality? I would have thought the gold coloration ;-) & Maxell name would make the former a better quality? Thanks. Different CD disks have different reflectivities for the burn/no burn conditions. The CD player has a calibration function that enables it to correctly recognize these conditions. Depending upon the design of the player, the ability to recognize disks with different reflectivities vary. Only a few years ago, it was common for many brands of CD players to fail to recognize CD-Rs, because insufficient range had been built into the calibration function. What you observe has more to do with the player than the disk. Gold as a reflective material has a signficant advantage for archival use. However, it is somewhat less reflective than aluminum. |
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#52
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CD Quality Difference in Player
Well, if we're interested in continuing this mini-thread, if you don't mind,
let me just ask this, based on my recollection of an earlier post - does your old Sony read CD-RW discs, as opposed to CD-R discs? Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... I believe CD-RW is Orange Book. "Mark D. Zacharias" wrote in message ... I think we're at cross purposes. Red Book doesn't define CD-RW as opposed to CD-R, does it? Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... Please read my post again. I said that AGC is a threshold detector function. It has nothing to do with laser diode power calibration. Sony players do nothing special with the laser diode. The AGC function provides variable threshold detection, which is what gives it the ability to read Orange Book. "Mark D. Zacharias" wrote in message ... And yet the laser power is not calibrated according to any disc reflectivity, merely to provide a constant laser current, which is virtually the same regardless of whether any laser light returns from the disc at all. In a multi-read model, which I will admit I have not studied, this may be different. Your old Sony however, isn't multi-read in the same sense as a modern CD-ROM device. It may just have the laser power turned up somewhat. The only unit I have seen which calibrated the laser output on playback was a karaoke model - unknown Chinese vendor. Viewing the HF pattern on a 'scope one could observe the laser "eye pattern" ramping up depending on the disc type. Your Sony does not do this. Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... "Mark D. Zacharias" wrote in message ... I was talking CD-R, not RW, haven't tried those in the older Sony's but I would be surprised. Lots of other units use the Sony pickups, and none of them boost the laser power based on reflectivity - a constant current is maintained as a voltage drop across a resistor, indicating a constant laser diode current, regardless of reflected signal received back to the diode pack. The APC (not ACG) transistor is mainly a switch, though as I say the current is kept nearly constant. Mark Z. I did not intend to imply that AGC is an adjustment of the laser diode. It is an adjustment of the threshold detector. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... Sorry, Mark, I can't agree. The following tech sheet http://www.sanyo.com/semiconductors/news/Vol66.pdf gives specs on the Sayn LA9251M, a common CD controller chip. Among the features provided is . Automatic follower operation (tracking gain and track detection level) Because lasers wear and output decays over time, calibration to the reflected signal at a particular point in the life in the product is essential. This feature is frequently referred to as AGC, and has been implemented with varying degrees of effectivenss in different players. For example, every Sony player I own, back to 1991, is multi-read capable, which means that it can read a CD-RW, which of all the available blanks differs the greatest from a pressing. Most other brands were, at least in the past, not nearly so good. It is remarkable that Sony built multi-read into their products long before CD-RW was in frequent use. I have the service manual for all my players, and none of these older, multiread capable units have either a calibration pot or a service mode. "Mark D. Zacharias" wrote in message ... With VERY few exceptions, audio CD players do not calibrate laser power automatically. Some are adjusted with physical potentiometers, some newer ones do it in a service mode using eeproms, but once set, the laser calibration is done. Focus is adjusted dynamically while playing, and of course during the focus search routine. Focus offset value is kept in memory until the next disc read operation so that if the PLAY button is pressed again, it can spin immediately without doing another focus search. Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... "Surinder Singh" wrote in message ... I play the CD's I burn in Phillipps Boombox. If I Maxell Gold CD-R it takes 20 seconds for the boom box to recognize the tracks and be ready to play it after inserting the CD. With Memorex 52x, it takes only 2 seconds for boom to recognize the tracks. Does it mean that Memorex is better quality? I would have thought the gold coloration ;-) & Maxell name would make the former a better quality? Thanks. Different CD disks have different reflectivities for the burn/no burn conditions. The CD player has a calibration function that enables it to correctly recognize these conditions. Depending upon the design of the player, the ability to recognize disks with different reflectivities vary. Only a few years ago, it was common for many brands of CD players to fail to recognize CD-Rs, because insufficient range had been built into the calibration function. What you observe has more to do with the player than the disk. Gold as a reflective material has a signficant advantage for archival use. However, it is somewhat less reflective than aluminum. |
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#53
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CD Quality Difference in Player
Well, if we're interested in continuing this mini-thread, if you don't mind,
let me just ask this, based on my recollection of an earlier post - does your old Sony read CD-RW discs, as opposed to CD-R discs? Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... I believe CD-RW is Orange Book. "Mark D. Zacharias" wrote in message ... I think we're at cross purposes. Red Book doesn't define CD-RW as opposed to CD-R, does it? Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... Please read my post again. I said that AGC is a threshold detector function. It has nothing to do with laser diode power calibration. Sony players do nothing special with the laser diode. The AGC function provides variable threshold detection, which is what gives it the ability to read Orange Book. "Mark D. Zacharias" wrote in message ... And yet the laser power is not calibrated according to any disc reflectivity, merely to provide a constant laser current, which is virtually the same regardless of whether any laser light returns from the disc at all. In a multi-read model, which I will admit I have not studied, this may be different. Your old Sony however, isn't multi-read in the same sense as a modern CD-ROM device. It may just have the laser power turned up somewhat. The only unit I have seen which calibrated the laser output on playback was a karaoke model - unknown Chinese vendor. Viewing the HF pattern on a 'scope one could observe the laser "eye pattern" ramping up depending on the disc type. Your Sony does not do this. Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... "Mark D. Zacharias" wrote in message ... I was talking CD-R, not RW, haven't tried those in the older Sony's but I would be surprised. Lots of other units use the Sony pickups, and none of them boost the laser power based on reflectivity - a constant current is maintained as a voltage drop across a resistor, indicating a constant laser diode current, regardless of reflected signal received back to the diode pack. The APC (not ACG) transistor is mainly a switch, though as I say the current is kept nearly constant. Mark Z. I did not intend to imply that AGC is an adjustment of the laser diode. It is an adjustment of the threshold detector. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... Sorry, Mark, I can't agree. The following tech sheet http://www.sanyo.com/semiconductors/news/Vol66.pdf gives specs on the Sayn LA9251M, a common CD controller chip. Among the features provided is . Automatic follower operation (tracking gain and track detection level) Because lasers wear and output decays over time, calibration to the reflected signal at a particular point in the life in the product is essential. This feature is frequently referred to as AGC, and has been implemented with varying degrees of effectivenss in different players. For example, every Sony player I own, back to 1991, is multi-read capable, which means that it can read a CD-RW, which of all the available blanks differs the greatest from a pressing. Most other brands were, at least in the past, not nearly so good. It is remarkable that Sony built multi-read into their products long before CD-RW was in frequent use. I have the service manual for all my players, and none of these older, multiread capable units have either a calibration pot or a service mode. "Mark D. Zacharias" wrote in message ... With VERY few exceptions, audio CD players do not calibrate laser power automatically. Some are adjusted with physical potentiometers, some newer ones do it in a service mode using eeproms, but once set, the laser calibration is done. Focus is adjusted dynamically while playing, and of course during the focus search routine. Focus offset value is kept in memory until the next disc read operation so that if the PLAY button is pressed again, it can spin immediately without doing another focus search. Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... "Surinder Singh" wrote in message ... I play the CD's I burn in Phillipps Boombox. If I Maxell Gold CD-R it takes 20 seconds for the boom box to recognize the tracks and be ready to play it after inserting the CD. With Memorex 52x, it takes only 2 seconds for boom to recognize the tracks. Does it mean that Memorex is better quality? I would have thought the gold coloration ;-) & Maxell name would make the former a better quality? Thanks. Different CD disks have different reflectivities for the burn/no burn conditions. The CD player has a calibration function that enables it to correctly recognize these conditions. Depending upon the design of the player, the ability to recognize disks with different reflectivities vary. Only a few years ago, it was common for many brands of CD players to fail to recognize CD-Rs, because insufficient range had been built into the calibration function. What you observe has more to do with the player than the disk. Gold as a reflective material has a signficant advantage for archival use. However, it is somewhat less reflective than aluminum. |
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#54
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CD Quality Difference in Player
Yes, I have the following players that play CD-RW:
qty. 2 of CDP-202ES qty. 1 of CDP-229ES "Mark D. Zacharias" wrote in message ... Well, if we're interested in continuing this mini-thread, if you don't mind, let me just ask this, based on my recollection of an earlier post - does your old Sony read CD-RW discs, as opposed to CD-R discs? Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... I believe CD-RW is Orange Book. "Mark D. Zacharias" wrote in message ... I think we're at cross purposes. Red Book doesn't define CD-RW as opposed to CD-R, does it? Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... Please read my post again. I said that AGC is a threshold detector function. It has nothing to do with laser diode power calibration. Sony players do nothing special with the laser diode. The AGC function provides variable threshold detection, which is what gives it the ability to read Orange Book. "Mark D. Zacharias" wrote in message ... And yet the laser power is not calibrated according to any disc reflectivity, merely to provide a constant laser current, which is virtually the same regardless of whether any laser light returns from the disc at all. In a multi-read model, which I will admit I have not studied, this may be different. Your old Sony however, isn't multi-read in the same sense as a modern CD-ROM device. It may just have the laser power turned up somewhat. The only unit I have seen which calibrated the laser output on playback was a karaoke model - unknown Chinese vendor. Viewing the HF pattern on a 'scope one could observe the laser "eye pattern" ramping up depending on the disc type. Your Sony does not do this. Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... "Mark D. Zacharias" wrote in message ... I was talking CD-R, not RW, haven't tried those in the older Sony's but I would be surprised. Lots of other units use the Sony pickups, and none of them boost the laser power based on reflectivity - a constant current is maintained as a voltage drop across a resistor, indicating a constant laser diode current, regardless of reflected signal received back to the diode pack. The APC (not ACG) transistor is mainly a switch, though as I say the current is kept nearly constant. Mark Z. I did not intend to imply that AGC is an adjustment of the laser diode. It is an adjustment of the threshold detector. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... Sorry, Mark, I can't agree. The following tech sheet http://www.sanyo.com/semiconductors/news/Vol66.pdf gives specs on the Sayn LA9251M, a common CD controller chip. Among the features provided is . Automatic follower operation (tracking gain and track detection level) Because lasers wear and output decays over time, calibration to the reflected signal at a particular point in the life in the product is essential. This feature is frequently referred to as AGC, and has been implemented with varying degrees of effectivenss in different players. For example, every Sony player I own, back to 1991, is multi-read capable, which means that it can read a CD-RW, which of all the available blanks differs the greatest from a pressing. Most other brands were, at least in the past, not nearly so good. It is remarkable that Sony built multi-read into their products long before CD-RW was in frequent use. I have the service manual for all my players, and none of these older, multiread capable units have either a calibration pot or a service mode. "Mark D. Zacharias" wrote in message ... With VERY few exceptions, audio CD players do not calibrate laser power automatically. Some are adjusted with physical potentiometers, some newer ones do it in a service mode using eeproms, but once set, the laser calibration is done. Focus is adjusted dynamically while playing, and of course during the focus search routine. Focus offset value is kept in memory until the next disc read operation so that if the PLAY button is pressed again, it can spin immediately without doing another focus search. Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... "Surinder Singh" wrote in message ... I play the CD's I burn in Phillipps Boombox. If I Maxell Gold CD-R it takes 20 seconds for the boom box to recognize the tracks and be ready to play it after inserting the CD. With Memorex 52x, it takes only 2 seconds for boom to recognize the tracks. Does it mean that Memorex is better quality? I would have thought the gold coloration ;-) & Maxell name would make the former a better quality? Thanks. Different CD disks have different reflectivities for the burn/no burn conditions. The CD player has a calibration function that enables it to correctly recognize these conditions. Depending upon the design of the player, the ability to recognize disks with different reflectivities vary. Only a few years ago, it was common for many brands of CD players to fail to recognize CD-Rs, because insufficient range had been built into the calibration function. What you observe has more to do with the player than the disk. Gold as a reflective material has a signficant advantage for archival use. However, it is somewhat less reflective than aluminum. |
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#55
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CD Quality Difference in Player
Yes, I have the following players that play CD-RW:
qty. 2 of CDP-202ES qty. 1 of CDP-229ES "Mark D. Zacharias" wrote in message ... Well, if we're interested in continuing this mini-thread, if you don't mind, let me just ask this, based on my recollection of an earlier post - does your old Sony read CD-RW discs, as opposed to CD-R discs? Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... I believe CD-RW is Orange Book. "Mark D. Zacharias" wrote in message ... I think we're at cross purposes. Red Book doesn't define CD-RW as opposed to CD-R, does it? Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... Please read my post again. I said that AGC is a threshold detector function. It has nothing to do with laser diode power calibration. Sony players do nothing special with the laser diode. The AGC function provides variable threshold detection, which is what gives it the ability to read Orange Book. "Mark D. Zacharias" wrote in message ... And yet the laser power is not calibrated according to any disc reflectivity, merely to provide a constant laser current, which is virtually the same regardless of whether any laser light returns from the disc at all. In a multi-read model, which I will admit I have not studied, this may be different. Your old Sony however, isn't multi-read in the same sense as a modern CD-ROM device. It may just have the laser power turned up somewhat. The only unit I have seen which calibrated the laser output on playback was a karaoke model - unknown Chinese vendor. Viewing the HF pattern on a 'scope one could observe the laser "eye pattern" ramping up depending on the disc type. Your Sony does not do this. Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... "Mark D. Zacharias" wrote in message ... I was talking CD-R, not RW, haven't tried those in the older Sony's but I would be surprised. Lots of other units use the Sony pickups, and none of them boost the laser power based on reflectivity - a constant current is maintained as a voltage drop across a resistor, indicating a constant laser diode current, regardless of reflected signal received back to the diode pack. The APC (not ACG) transistor is mainly a switch, though as I say the current is kept nearly constant. Mark Z. I did not intend to imply that AGC is an adjustment of the laser diode. It is an adjustment of the threshold detector. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... Sorry, Mark, I can't agree. The following tech sheet http://www.sanyo.com/semiconductors/news/Vol66.pdf gives specs on the Sayn LA9251M, a common CD controller chip. Among the features provided is . Automatic follower operation (tracking gain and track detection level) Because lasers wear and output decays over time, calibration to the reflected signal at a particular point in the life in the product is essential. This feature is frequently referred to as AGC, and has been implemented with varying degrees of effectivenss in different players. For example, every Sony player I own, back to 1991, is multi-read capable, which means that it can read a CD-RW, which of all the available blanks differs the greatest from a pressing. Most other brands were, at least in the past, not nearly so good. It is remarkable that Sony built multi-read into their products long before CD-RW was in frequent use. I have the service manual for all my players, and none of these older, multiread capable units have either a calibration pot or a service mode. "Mark D. Zacharias" wrote in message ... With VERY few exceptions, audio CD players do not calibrate laser power automatically. Some are adjusted with physical potentiometers, some newer ones do it in a service mode using eeproms, but once set, the laser calibration is done. Focus is adjusted dynamically while playing, and of course during the focus search routine. Focus offset value is kept in memory until the next disc read operation so that if the PLAY button is pressed again, it can spin immediately without doing another focus search. Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... "Surinder Singh" wrote in message ... I play the CD's I burn in Phillipps Boombox. If I Maxell Gold CD-R it takes 20 seconds for the boom box to recognize the tracks and be ready to play it after inserting the CD. With Memorex 52x, it takes only 2 seconds for boom to recognize the tracks. Does it mean that Memorex is better quality? I would have thought the gold coloration ;-) & Maxell name would make the former a better quality? Thanks. Different CD disks have different reflectivities for the burn/no burn conditions. The CD player has a calibration function that enables it to correctly recognize these conditions. Depending upon the design of the player, the ability to recognize disks with different reflectivities vary. Only a few years ago, it was common for many brands of CD players to fail to recognize CD-Rs, because insufficient range had been built into the calibration function. What you observe has more to do with the player than the disk. Gold as a reflective material has a signficant advantage for archival use. However, it is somewhat less reflective than aluminum. |
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#56
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CD Quality Difference in Player
Yes, I have the following players that play CD-RW:
qty. 2 of CDP-202ES qty. 1 of CDP-229ES "Mark D. Zacharias" wrote in message ... Well, if we're interested in continuing this mini-thread, if you don't mind, let me just ask this, based on my recollection of an earlier post - does your old Sony read CD-RW discs, as opposed to CD-R discs? Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... I believe CD-RW is Orange Book. "Mark D. Zacharias" wrote in message ... I think we're at cross purposes. Red Book doesn't define CD-RW as opposed to CD-R, does it? Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... Please read my post again. I said that AGC is a threshold detector function. It has nothing to do with laser diode power calibration. Sony players do nothing special with the laser diode. The AGC function provides variable threshold detection, which is what gives it the ability to read Orange Book. "Mark D. Zacharias" wrote in message ... And yet the laser power is not calibrated according to any disc reflectivity, merely to provide a constant laser current, which is virtually the same regardless of whether any laser light returns from the disc at all. In a multi-read model, which I will admit I have not studied, this may be different. Your old Sony however, isn't multi-read in the same sense as a modern CD-ROM device. It may just have the laser power turned up somewhat. The only unit I have seen which calibrated the laser output on playback was a karaoke model - unknown Chinese vendor. Viewing the HF pattern on a 'scope one could observe the laser "eye pattern" ramping up depending on the disc type. Your Sony does not do this. Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... "Mark D. Zacharias" wrote in message ... I was talking CD-R, not RW, haven't tried those in the older Sony's but I would be surprised. Lots of other units use the Sony pickups, and none of them boost the laser power based on reflectivity - a constant current is maintained as a voltage drop across a resistor, indicating a constant laser diode current, regardless of reflected signal received back to the diode pack. The APC (not ACG) transistor is mainly a switch, though as I say the current is kept nearly constant. Mark Z. I did not intend to imply that AGC is an adjustment of the laser diode. It is an adjustment of the threshold detector. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... Sorry, Mark, I can't agree. The following tech sheet http://www.sanyo.com/semiconductors/news/Vol66.pdf gives specs on the Sayn LA9251M, a common CD controller chip. Among the features provided is . Automatic follower operation (tracking gain and track detection level) Because lasers wear and output decays over time, calibration to the reflected signal at a particular point in the life in the product is essential. This feature is frequently referred to as AGC, and has been implemented with varying degrees of effectivenss in different players. For example, every Sony player I own, back to 1991, is multi-read capable, which means that it can read a CD-RW, which of all the available blanks differs the greatest from a pressing. Most other brands were, at least in the past, not nearly so good. It is remarkable that Sony built multi-read into their products long before CD-RW was in frequent use. I have the service manual for all my players, and none of these older, multiread capable units have either a calibration pot or a service mode. "Mark D. Zacharias" wrote in message ... With VERY few exceptions, audio CD players do not calibrate laser power automatically. Some are adjusted with physical potentiometers, some newer ones do it in a service mode using eeproms, but once set, the laser calibration is done. Focus is adjusted dynamically while playing, and of course during the focus search routine. Focus offset value is kept in memory until the next disc read operation so that if the PLAY button is pressed again, it can spin immediately without doing another focus search. Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... "Surinder Singh" wrote in message ... I play the CD's I burn in Phillipps Boombox. If I Maxell Gold CD-R it takes 20 seconds for the boom box to recognize the tracks and be ready to play it after inserting the CD. With Memorex 52x, it takes only 2 seconds for boom to recognize the tracks. Does it mean that Memorex is better quality? I would have thought the gold coloration ;-) & Maxell name would make the former a better quality? Thanks. Different CD disks have different reflectivities for the burn/no burn conditions. The CD player has a calibration function that enables it to correctly recognize these conditions. Depending upon the design of the player, the ability to recognize disks with different reflectivities vary. Only a few years ago, it was common for many brands of CD players to fail to recognize CD-Rs, because insufficient range had been built into the calibration function. What you observe has more to do with the player than the disk. Gold as a reflective material has a signficant advantage for archival use. However, it is somewhat less reflective than aluminum. |
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#57
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CD Quality Difference in Player
Yes, I have the following players that play CD-RW:
qty. 2 of CDP-202ES qty. 1 of CDP-229ES "Mark D. Zacharias" wrote in message ... Well, if we're interested in continuing this mini-thread, if you don't mind, let me just ask this, based on my recollection of an earlier post - does your old Sony read CD-RW discs, as opposed to CD-R discs? Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... I believe CD-RW is Orange Book. "Mark D. Zacharias" wrote in message ... I think we're at cross purposes. Red Book doesn't define CD-RW as opposed to CD-R, does it? Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... Please read my post again. I said that AGC is a threshold detector function. It has nothing to do with laser diode power calibration. Sony players do nothing special with the laser diode. The AGC function provides variable threshold detection, which is what gives it the ability to read Orange Book. "Mark D. Zacharias" wrote in message ... And yet the laser power is not calibrated according to any disc reflectivity, merely to provide a constant laser current, which is virtually the same regardless of whether any laser light returns from the disc at all. In a multi-read model, which I will admit I have not studied, this may be different. Your old Sony however, isn't multi-read in the same sense as a modern CD-ROM device. It may just have the laser power turned up somewhat. The only unit I have seen which calibrated the laser output on playback was a karaoke model - unknown Chinese vendor. Viewing the HF pattern on a 'scope one could observe the laser "eye pattern" ramping up depending on the disc type. Your Sony does not do this. Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... "Mark D. Zacharias" wrote in message ... I was talking CD-R, not RW, haven't tried those in the older Sony's but I would be surprised. Lots of other units use the Sony pickups, and none of them boost the laser power based on reflectivity - a constant current is maintained as a voltage drop across a resistor, indicating a constant laser diode current, regardless of reflected signal received back to the diode pack. The APC (not ACG) transistor is mainly a switch, though as I say the current is kept nearly constant. Mark Z. I did not intend to imply that AGC is an adjustment of the laser diode. It is an adjustment of the threshold detector. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... Sorry, Mark, I can't agree. The following tech sheet http://www.sanyo.com/semiconductors/news/Vol66.pdf gives specs on the Sayn LA9251M, a common CD controller chip. Among the features provided is . Automatic follower operation (tracking gain and track detection level) Because lasers wear and output decays over time, calibration to the reflected signal at a particular point in the life in the product is essential. This feature is frequently referred to as AGC, and has been implemented with varying degrees of effectivenss in different players. For example, every Sony player I own, back to 1991, is multi-read capable, which means that it can read a CD-RW, which of all the available blanks differs the greatest from a pressing. Most other brands were, at least in the past, not nearly so good. It is remarkable that Sony built multi-read into their products long before CD-RW was in frequent use. I have the service manual for all my players, and none of these older, multiread capable units have either a calibration pot or a service mode. "Mark D. Zacharias" wrote in message ... With VERY few exceptions, audio CD players do not calibrate laser power automatically. Some are adjusted with physical potentiometers, some newer ones do it in a service mode using eeproms, but once set, the laser calibration is done. Focus is adjusted dynamically while playing, and of course during the focus search routine. Focus offset value is kept in memory until the next disc read operation so that if the PLAY button is pressed again, it can spin immediately without doing another focus search. Mark Z. -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "Robert Morein" wrote in message ... "Surinder Singh" wrote in message ... I play the CD's I burn in Phillipps Boombox. If I Maxell Gold CD-R it takes 20 seconds for the boom box to recognize the tracks and be ready to play it after inserting the CD. With Memorex 52x, it takes only 2 seconds for boom to recognize the tracks. Does it mean that Memorex is better quality? I would have thought the gold coloration ;-) & Maxell name would make the former a better quality? Thanks. Different CD disks have different reflectivities for the burn/no burn conditions. The CD player has a calibration function that enables it to correctly recognize these conditions. Depending upon the design of the player, the ability to recognize disks with different reflectivities vary. Only a few years ago, it was common for many brands of CD players to fail to recognize CD-Rs, because insufficient range had been built into the calibration function. What you observe has more to do with the player than the disk. Gold as a reflective material has a signficant advantage for archival use. However, it is somewhat less reflective than aluminum. |
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#58
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CD Quality Difference in Player
Mark D. Zacharias wrote:
Well, if we're interested in continuing this mini-thread, if you don't mind, let me just ask this, based on my recollection of an earlier post - does your old Sony read CD-RW discs, as opposed to CD-R discs? Mark Z. If your CD player can read a CDRW, then it's got quite strong laser beam. CDRW are the hardest to read, then come CDRs, then the regular audio CDs you buy at places like Tower Records. From my experience with CDRWs, they are significantly harder to read than CDRs when you go from player to player. If I make a CD, I want to know that it will play in a CD boombox, my car stereo, my home player, etc, without difficulty. With CDRWs, usually one of those items misses. Couple that with the fact that they take longer to burn and cost more when compared to CDRs, I gave up on CDRWs. I just burn CDRs as tests. Cost per CDR is cheaper than even a TDK D90 normal cassette, so no biggie. CD |
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#59
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CD Quality Difference in Player
Mark D. Zacharias wrote:
Well, if we're interested in continuing this mini-thread, if you don't mind, let me just ask this, based on my recollection of an earlier post - does your old Sony read CD-RW discs, as opposed to CD-R discs? Mark Z. If your CD player can read a CDRW, then it's got quite strong laser beam. CDRW are the hardest to read, then come CDRs, then the regular audio CDs you buy at places like Tower Records. From my experience with CDRWs, they are significantly harder to read than CDRs when you go from player to player. If I make a CD, I want to know that it will play in a CD boombox, my car stereo, my home player, etc, without difficulty. With CDRWs, usually one of those items misses. Couple that with the fact that they take longer to burn and cost more when compared to CDRs, I gave up on CDRWs. I just burn CDRs as tests. Cost per CDR is cheaper than even a TDK D90 normal cassette, so no biggie. CD |
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#60
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CD Quality Difference in Player
Mark D. Zacharias wrote:
Well, if we're interested in continuing this mini-thread, if you don't mind, let me just ask this, based on my recollection of an earlier post - does your old Sony read CD-RW discs, as opposed to CD-R discs? Mark Z. If your CD player can read a CDRW, then it's got quite strong laser beam. CDRW are the hardest to read, then come CDRs, then the regular audio CDs you buy at places like Tower Records. From my experience with CDRWs, they are significantly harder to read than CDRs when you go from player to player. If I make a CD, I want to know that it will play in a CD boombox, my car stereo, my home player, etc, without difficulty. With CDRWs, usually one of those items misses. Couple that with the fact that they take longer to burn and cost more when compared to CDRs, I gave up on CDRWs. I just burn CDRs as tests. Cost per CDR is cheaper than even a TDK D90 normal cassette, so no biggie. CD |
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#61
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CD Quality Difference in Player
Mark D. Zacharias wrote:
Well, if we're interested in continuing this mini-thread, if you don't mind, let me just ask this, based on my recollection of an earlier post - does your old Sony read CD-RW discs, as opposed to CD-R discs? Mark Z. If your CD player can read a CDRW, then it's got quite strong laser beam. CDRW are the hardest to read, then come CDRs, then the regular audio CDs you buy at places like Tower Records. From my experience with CDRWs, they are significantly harder to read than CDRs when you go from player to player. If I make a CD, I want to know that it will play in a CD boombox, my car stereo, my home player, etc, without difficulty. With CDRWs, usually one of those items misses. Couple that with the fact that they take longer to burn and cost more when compared to CDRs, I gave up on CDRWs. I just burn CDRs as tests. Cost per CDR is cheaper than even a TDK D90 normal cassette, so no biggie. CD |
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#62
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CD Quality Difference in Player
"Codifus" wrote in message et... Mark D. Zacharias wrote: Well, if we're interested in continuing this mini-thread, if you don't mind, let me just ask this, based on my recollection of an earlier post - does your old Sony read CD-RW discs, as opposed to CD-R discs? Mark Z. If your CD player can read a CDRW, then it's got quite strong laser beam. It is not a question of beam strength. Photodetectors can be incredibly sensitive, far more than required to sense the reflection from a CD of any type. The problem for the designer is to determine what level of reflectivity is equivalent to a transition, and what level is the base reflectivity level. This requires what is commonly referred to as an AGC circuit, though it may go by different names. It determines the threshold that applies to the particular disk. Although this is a simple circuit, designers originally made AGC circuits that could accomodate the range of various CD pressings. As the available types of media diversified, AGC circuits were required to function over a wider range. Exhibiting an unusual degree of foresight, Sony CD players were equipped with AGC circuits capable of handling media that would not be in common use for years. Other manufacturers, particularly Panasonic, lagged developments in media. |
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#63
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CD Quality Difference in Player
"Codifus" wrote in message et... Mark D. Zacharias wrote: Well, if we're interested in continuing this mini-thread, if you don't mind, let me just ask this, based on my recollection of an earlier post - does your old Sony read CD-RW discs, as opposed to CD-R discs? Mark Z. If your CD player can read a CDRW, then it's got quite strong laser beam. It is not a question of beam strength. Photodetectors can be incredibly sensitive, far more than required to sense the reflection from a CD of any type. The problem for the designer is to determine what level of reflectivity is equivalent to a transition, and what level is the base reflectivity level. This requires what is commonly referred to as an AGC circuit, though it may go by different names. It determines the threshold that applies to the particular disk. Although this is a simple circuit, designers originally made AGC circuits that could accomodate the range of various CD pressings. As the available types of media diversified, AGC circuits were required to function over a wider range. Exhibiting an unusual degree of foresight, Sony CD players were equipped with AGC circuits capable of handling media that would not be in common use for years. Other manufacturers, particularly Panasonic, lagged developments in media. |
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#64
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CD Quality Difference in Player
"Codifus" wrote in message et... Mark D. Zacharias wrote: Well, if we're interested in continuing this mini-thread, if you don't mind, let me just ask this, based on my recollection of an earlier post - does your old Sony read CD-RW discs, as opposed to CD-R discs? Mark Z. If your CD player can read a CDRW, then it's got quite strong laser beam. It is not a question of beam strength. Photodetectors can be incredibly sensitive, far more than required to sense the reflection from a CD of any type. The problem for the designer is to determine what level of reflectivity is equivalent to a transition, and what level is the base reflectivity level. This requires what is commonly referred to as an AGC circuit, though it may go by different names. It determines the threshold that applies to the particular disk. Although this is a simple circuit, designers originally made AGC circuits that could accomodate the range of various CD pressings. As the available types of media diversified, AGC circuits were required to function over a wider range. Exhibiting an unusual degree of foresight, Sony CD players were equipped with AGC circuits capable of handling media that would not be in common use for years. Other manufacturers, particularly Panasonic, lagged developments in media. |
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#65
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CD Quality Difference in Player
"Codifus" wrote in message et... Mark D. Zacharias wrote: Well, if we're interested in continuing this mini-thread, if you don't mind, let me just ask this, based on my recollection of an earlier post - does your old Sony read CD-RW discs, as opposed to CD-R discs? Mark Z. If your CD player can read a CDRW, then it's got quite strong laser beam. It is not a question of beam strength. Photodetectors can be incredibly sensitive, far more than required to sense the reflection from a CD of any type. The problem for the designer is to determine what level of reflectivity is equivalent to a transition, and what level is the base reflectivity level. This requires what is commonly referred to as an AGC circuit, though it may go by different names. It determines the threshold that applies to the particular disk. Although this is a simple circuit, designers originally made AGC circuits that could accomodate the range of various CD pressings. As the available types of media diversified, AGC circuits were required to function over a wider range. Exhibiting an unusual degree of foresight, Sony CD players were equipped with AGC circuits capable of handling media that would not be in common use for years. Other manufacturers, particularly Panasonic, lagged developments in media. |
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#66
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CD Quality Difference in Player
I need to give this a try on some old Sonys.
mz -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "WorldJAZZ" wrote in message ... "Codifus" wrote in message et... Mark D. Zacharias wrote: Well, if we're interested in continuing this mini-thread, if you don't mind, let me just ask this, based on my recollection of an earlier post - does your old Sony read CD-RW discs, as opposed to CD-R discs? Mark Z. If your CD player can read a CDRW, then it's got quite strong laser beam. It is not a question of beam strength. Photodetectors can be incredibly sensitive, far more than required to sense the reflection from a CD of any type. The problem for the designer is to determine what level of reflectivity is equivalent to a transition, and what level is the base reflectivity level. This requires what is commonly referred to as an AGC circuit, though it may go by different names. It determines the threshold that applies to the particular disk. Although this is a simple circuit, designers originally made AGC circuits that could accomodate the range of various CD pressings. As the available types of media diversified, AGC circuits were required to function over a wider range. Exhibiting an unusual degree of foresight, Sony CD players were equipped with AGC circuits capable of handling media that would not be in common use for years. Other manufacturers, particularly Panasonic, lagged developments in media. |
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#67
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CD Quality Difference in Player
I need to give this a try on some old Sonys.
mz -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "WorldJAZZ" wrote in message ... "Codifus" wrote in message et... Mark D. Zacharias wrote: Well, if we're interested in continuing this mini-thread, if you don't mind, let me just ask this, based on my recollection of an earlier post - does your old Sony read CD-RW discs, as opposed to CD-R discs? Mark Z. If your CD player can read a CDRW, then it's got quite strong laser beam. It is not a question of beam strength. Photodetectors can be incredibly sensitive, far more than required to sense the reflection from a CD of any type. The problem for the designer is to determine what level of reflectivity is equivalent to a transition, and what level is the base reflectivity level. This requires what is commonly referred to as an AGC circuit, though it may go by different names. It determines the threshold that applies to the particular disk. Although this is a simple circuit, designers originally made AGC circuits that could accomodate the range of various CD pressings. As the available types of media diversified, AGC circuits were required to function over a wider range. Exhibiting an unusual degree of foresight, Sony CD players were equipped with AGC circuits capable of handling media that would not be in common use for years. Other manufacturers, particularly Panasonic, lagged developments in media. |
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#68
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CD Quality Difference in Player
I need to give this a try on some old Sonys.
mz -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "WorldJAZZ" wrote in message ... "Codifus" wrote in message et... Mark D. Zacharias wrote: Well, if we're interested in continuing this mini-thread, if you don't mind, let me just ask this, based on my recollection of an earlier post - does your old Sony read CD-RW discs, as opposed to CD-R discs? Mark Z. If your CD player can read a CDRW, then it's got quite strong laser beam. It is not a question of beam strength. Photodetectors can be incredibly sensitive, far more than required to sense the reflection from a CD of any type. The problem for the designer is to determine what level of reflectivity is equivalent to a transition, and what level is the base reflectivity level. This requires what is commonly referred to as an AGC circuit, though it may go by different names. It determines the threshold that applies to the particular disk. Although this is a simple circuit, designers originally made AGC circuits that could accomodate the range of various CD pressings. As the available types of media diversified, AGC circuits were required to function over a wider range. Exhibiting an unusual degree of foresight, Sony CD players were equipped with AGC circuits capable of handling media that would not be in common use for years. Other manufacturers, particularly Panasonic, lagged developments in media. |
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#69
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CD Quality Difference in Player
I need to give this a try on some old Sonys.
mz -- Please reply only to Group. I regret this is necessary. Viruses and spam have rendered my regular e-mail address useless. "WorldJAZZ" wrote in message ... "Codifus" wrote in message et... Mark D. Zacharias wrote: Well, if we're interested in continuing this mini-thread, if you don't mind, let me just ask this, based on my recollection of an earlier post - does your old Sony read CD-RW discs, as opposed to CD-R discs? Mark Z. If your CD player can read a CDRW, then it's got quite strong laser beam. It is not a question of beam strength. Photodetectors can be incredibly sensitive, far more than required to sense the reflection from a CD of any type. The problem for the designer is to determine what level of reflectivity is equivalent to a transition, and what level is the base reflectivity level. This requires what is commonly referred to as an AGC circuit, though it may go by different names. It determines the threshold that applies to the particular disk. Although this is a simple circuit, designers originally made AGC circuits that could accomodate the range of various CD pressings. As the available types of media diversified, AGC circuits were required to function over a wider range. Exhibiting an unusual degree of foresight, Sony CD players were equipped with AGC circuits capable of handling media that would not be in common use for years. Other manufacturers, particularly Panasonic, lagged developments in media. |
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#70
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CD Quality Difference in Player
WorldJAZZ wrote:
"Codifus" wrote in message et... Mark D. Zacharias wrote: Well, if we're interested in continuing this mini-thread, if you don't mind, let me just ask this, based on my recollection of an earlier post - does your old Sony read CD-RW discs, as opposed to CD-R discs? Mark Z. If your CD player can read a CDRW, then it's got quite strong laser beam. It is not a question of beam strength. Photodetectors can be incredibly sensitive, far more than required to sense the reflection from a CD of any type. The problem for the designer is to determine what level of reflectivity is equivalent to a transition, and what level is the base reflectivity level. This requires what is commonly referred to as an AGC circuit, though it may go by different names. It determines the threshold that applies to the particular disk. Although this is a simple circuit, designers originally made AGC circuits that could accomodate the range of various CD pressings. As the available types of media diversified, AGC circuits were required to function over a wider range. Exhibiting an unusual degree of foresight, Sony CD players were equipped with AGC circuits capable of handling media that would not be in common use for years. Other manufacturers, particularly Panasonic, lagged developments in media. Nice. I wish my old Sony player was still functional. It would have been nice to try out a CDRW on it. Anyhow, since CDRWs are still the most finicky, these well adjusted AGC cicuits could only benefit someone who buys all Sony CD players, one in their car, home, walkman, etc. CD |
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#71
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CD Quality Difference in Player
WorldJAZZ wrote:
"Codifus" wrote in message et... Mark D. Zacharias wrote: Well, if we're interested in continuing this mini-thread, if you don't mind, let me just ask this, based on my recollection of an earlier post - does your old Sony read CD-RW discs, as opposed to CD-R discs? Mark Z. If your CD player can read a CDRW, then it's got quite strong laser beam. It is not a question of beam strength. Photodetectors can be incredibly sensitive, far more than required to sense the reflection from a CD of any type. The problem for the designer is to determine what level of reflectivity is equivalent to a transition, and what level is the base reflectivity level. This requires what is commonly referred to as an AGC circuit, though it may go by different names. It determines the threshold that applies to the particular disk. Although this is a simple circuit, designers originally made AGC circuits that could accomodate the range of various CD pressings. As the available types of media diversified, AGC circuits were required to function over a wider range. Exhibiting an unusual degree of foresight, Sony CD players were equipped with AGC circuits capable of handling media that would not be in common use for years. Other manufacturers, particularly Panasonic, lagged developments in media. Nice. I wish my old Sony player was still functional. It would have been nice to try out a CDRW on it. Anyhow, since CDRWs are still the most finicky, these well adjusted AGC cicuits could only benefit someone who buys all Sony CD players, one in their car, home, walkman, etc. CD |
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#72
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CD Quality Difference in Player
WorldJAZZ wrote:
"Codifus" wrote in message et... Mark D. Zacharias wrote: Well, if we're interested in continuing this mini-thread, if you don't mind, let me just ask this, based on my recollection of an earlier post - does your old Sony read CD-RW discs, as opposed to CD-R discs? Mark Z. If your CD player can read a CDRW, then it's got quite strong laser beam. It is not a question of beam strength. Photodetectors can be incredibly sensitive, far more than required to sense the reflection from a CD of any type. The problem for the designer is to determine what level of reflectivity is equivalent to a transition, and what level is the base reflectivity level. This requires what is commonly referred to as an AGC circuit, though it may go by different names. It determines the threshold that applies to the particular disk. Although this is a simple circuit, designers originally made AGC circuits that could accomodate the range of various CD pressings. As the available types of media diversified, AGC circuits were required to function over a wider range. Exhibiting an unusual degree of foresight, Sony CD players were equipped with AGC circuits capable of handling media that would not be in common use for years. Other manufacturers, particularly Panasonic, lagged developments in media. Nice. I wish my old Sony player was still functional. It would have been nice to try out a CDRW on it. Anyhow, since CDRWs are still the most finicky, these well adjusted AGC cicuits could only benefit someone who buys all Sony CD players, one in their car, home, walkman, etc. CD |
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#73
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CD Quality Difference in Player
WorldJAZZ wrote:
"Codifus" wrote in message et... Mark D. Zacharias wrote: Well, if we're interested in continuing this mini-thread, if you don't mind, let me just ask this, based on my recollection of an earlier post - does your old Sony read CD-RW discs, as opposed to CD-R discs? Mark Z. If your CD player can read a CDRW, then it's got quite strong laser beam. It is not a question of beam strength. Photodetectors can be incredibly sensitive, far more than required to sense the reflection from a CD of any type. The problem for the designer is to determine what level of reflectivity is equivalent to a transition, and what level is the base reflectivity level. This requires what is commonly referred to as an AGC circuit, though it may go by different names. It determines the threshold that applies to the particular disk. Although this is a simple circuit, designers originally made AGC circuits that could accomodate the range of various CD pressings. As the available types of media diversified, AGC circuits were required to function over a wider range. Exhibiting an unusual degree of foresight, Sony CD players were equipped with AGC circuits capable of handling media that would not be in common use for years. Other manufacturers, particularly Panasonic, lagged developments in media. Nice. I wish my old Sony player was still functional. It would have been nice to try out a CDRW on it. Anyhow, since CDRWs are still the most finicky, these well adjusted AGC cicuits could only benefit someone who buys all Sony CD players, one in their car, home, walkman, etc. CD |
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