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#1
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System warm-up
Hi,
My hi-fi sounds great sometimes and not others. I am told that it needs an hour's warm-up and this could fit with the times it has sounded good. For example, great one evening but poor the next morning. I leave the electronics on but not playing. Is there a CD that can be played to loosen the system up? I suspect the speakers most. Bass extension is particularly absent at times. Any suggestions as to whether playing a very low frequency sine wave or similar could do the trick? -- TIA, James |
#2
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System warm-up
James Harris wrote:
My hi-fi sounds great sometimes and not others. Most likely causes would be your state of mind and your selection of music to listen to. I am told that it needs an hour's warm-up and this could fit with the times it has sounded good. If your system has some technical defect, then warming up could deal with the problem. In general audio systems are up to peak performance within a minute or less of commencment of use. For example, great one evening but poor the next morning. Your system could have a defect that makes it extraordinarly sensitive to operating temperature. I leave the electronics on but not playing. Is there a CD that can be played to loosen the system up? Nothing special should be required. I suspect the speakers most. Bass extension is particularly absent at times. In fact, the cause could be anything else in the system. Any suggestions as to whether playing a very low frequency sine wave or similar could do the trick? Not if your system is in good shape. |
#3
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System warm-up
"Arny Krueger" wrote in message ... James Harris wrote: My hi-fi sounds great sometimes and not others. Most likely causes would be your state of mind and your selection of music to listen to. I am told that it needs an hour's warm-up and this could fit with the times it has sounded good. If your system has some technical defect, then warming up could deal with the problem. In general audio systems are up to peak performance within a minute or less of commencment of use. For example, great one evening but poor the next morning. Your system could have a defect that makes it extraordinarly sensitive to operating temperature. More like changes in your hearing. Have you ever noticed that you set your clock-radio in sleep mode and go to sleep listening to the news or whatever fairly quietly, but when it wakes you in the morning it is deafeningly loud? Your hearing is done by a 'field' of very fine hairs inside your ear canal that flex with the air movement that we call sound. During the day ambient noise, from traffic, being inside a moving car/train/plane, and/or workplace noise, etc etc cause the hairs to get tired and somewhat slow to move - rather like a lawn on which the kids have been playing all day - so your hearing sensitivity decays. Whilst you sleep in a relatively quiet environment the hairs rejuvenate so that come the morning your hearing is vastly more sensitive - the grass perks up again. The hairs also deplete in quantity and flexibility with age, hence why in most people high frequency sensitivity decays as you get older. Deafness, especially that induced by working in a high-moise environment with protection, occurs when the hairs stay tired and cannot restore themselves - i.e. the grass has had neither food or water and stays 'flat.' In terms of hi-fi, in the morning you probably don't play it quite so loud which affects both how the speaker sounds in itself and how it interacts with the room, thus affecting the subjective sound quality. Subjectivity is by definition opinion, so how you hear something may and most probably differ from how someone else hears it and hence why I think, for example, that the Wharfedale 8.3 is awful, but What Hi-Fi think it is the best thing since sliced bread! -- Woody |
#4
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System warm-up
"Woody" wrote in message ... "Arny Krueger" wrote in message ... James Harris wrote: My hi-fi sounds great sometimes and not others. Most likely causes would be your state of mind and your selection of music to listen to. I am told that it needs an hour's warm-up and this could fit with the times it has sounded good. If your system has some technical defect, then warming up could deal with the problem. In general audio systems are up to peak performance within a minute or less of commencment of use. For example, great one evening but poor the next morning. Your system could have a defect that makes it extraordinarly sensitive to operating temperature. More like changes in your hearing. Have you ever noticed that you set your clock-radio in sleep mode and go to sleep listening to the news or whatever fairly quietly, but when it wakes you in the morning it is deafeningly loud? My ears are literally congealed in the morning. As the day wears on, they loosen up. The tissues of the ears live in a world of thick, goopy liquid, the consistency of which varies from hour to hour and day to day. |
#5
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System warm-up
"Woody" wrote in message ...
---snip--- Your hearing is done by a 'field' of very fine hairs inside your ear canal that flex with the air movement that we call sound. ---snip--- An otherwise excellent post, but just to avoid unintentionally misleading anyone, those hairs flex indirectly with the air movement (localized variations in pressure) which we call sound. Those hairs are in a fluid-filled chamber to which the vibrations of your eardrum caused by sound are coupled through some little bitty bones. The air doesn't move those hairs directly, and as far as I know they have absolutely nothing to do with those "other ear hairs" that show up and start growing like crabgrass somewhere in middle age. |
#6
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System warm-up
From: "James Harris" no.email.please
Date: 4/13/2004 4:06 PM Pacific Standard Time Message-id: Hi, My hi-fi sounds great sometimes and not others. I am told that it needs an hour's warm-up and this could fit with the times it has sounded good. For example, great one evening but poor the next morning. I leave the electronics on but not playing. Maybe you could give us the specifics on your system. Is there a CD that can be played to loosen the system up? I suspect the speakers most. Bass extension is particularly absent at times. Any suggestions as to whether playing a very low frequency sine wave or similar could do the trick? Check Acoustic Sounds or Music Direct for a number of test and diagnostic CDs. I doubt that Bass extension would be that affected by any sort of warm up. |
#7
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System warm-up
"S888Wheel" wrote in message
... snip My hi-fi sounds great sometimes and not others. snip Maybe you could give us the specifics on your system. Nad C541i as transport, Meridian 203 DAC, Rotel RA-02 amp, Dynaudio Audience 62 floorstand speakers Chord Optichord digital link, Audioquest Python interconnects, Atlas 2.0 speaker cable, Atacama Equinox rack The dealer advised a 30 to 60 minute warmup before each listening session - which is a pain and I'm not convinced that the improved sound quality follows such a warmup. The improvement seems random - and unexpected. Maybe mains problems? The sonic difference to the bass is quite clear. Forgive the adjectives but when it's not working well the sound is OK but 'thin' and lacks energy. When it works well the bass is rich and the sound fuller and more musical at the same volume. It even sounds good with the volume lower. The Audioquest Pythons were the last addition. I wasn't happy with the system - it didn't have the clarity - until they were added to replace Atlas Voyagers. Does the kit list above give any clues as to why the sound would change? (BTW, thanks too for your suggestions on test CDs.) |
#8
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System warm-up
From: "James Harris" no.email.please
Date: 4/15/2004 1:31 PM Pacific Standard Time Message-id: "S888Wheel" wrote in message ... snip My hi-fi sounds great sometimes and not others. snip Maybe you could give us the specifics on your system. Nad C541i as transport, Meridian 203 DAC, Rotel RA-02 amp, Dynaudio Audience 62 floorstand speakers Chord Optichord digital link, Audioquest Python interconnects, Atlas 2.0 speaker cable, Atacama Equinox rack The dealer advised a 30 to 60 minute warmup before each listening session - which is a pain and I'm not convinced that the improved sound quality follows such a warmup. Well it doesn't sound like a true warm up issue. The improvement seems random - and unexpected. Maybe mains problems? The sonic difference to the bass is quite clear. Forgive the adjectives but when it's not working well the sound is OK but 'thin' and lacks energy. When it works well the bass is rich and the sound fuller and more musical at the same volume. It even sounds good with the volume lower. I don't see how any kind of warm up could ever make that kind of difference with your equipment. The Audioquest Pythons were the last addition. I wasn't happy with the system - it didn't have the clarity - until they were added to replace Atlas Voyagers. Does the kit list above give any clues as to why the sound would change? No. Not at all. I'd say there may be something malfunctioning. (BTW, thanks too for your suggestions on test CDs.) Quite welcome. |
#9
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System warm-up
James Harris wrote:
"S888Wheel" wrote in message ... snip My hi-fi sounds great sometimes and not others. snip Maybe you could give us the specifics on your system. Nad C541i as transport, Meridian 203 DAC, Rotel RA-02 amp, Dynaudio Audience 62 floorstand speakers James, I am curious. The Meridian DAC is at least 12 years old. I would have thought that the newer Burr Brown DACs in the NAD would measure better and produce "better" sound than the older Philips DAC in the Meridian (is it multibit or bitstream?) |
#10
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System warm-up
In article ,
Tat Chan wrote: James Harris wrote: Nad C541i as transport, Meridian 203 DAC, Rotel RA-02 amp, Dynaudio Audience 62 floorstand speakers James, I am curious. The Meridian DAC is at least 12 years old. I would have thought that the newer Burr Brown DACs in the NAD would measure better and produce "better" sound than the older Philips DAC in the Meridian (is it multibit or bitstream?) I doubt that this is simply a matter of choice of DAC chip. Other influences will include the PSU, buffering, differences in filtering, etc. FWIW I remain a fan of the Meridian 263 and 563, (as well as the Quad 67) despite them being 'out of favour' for a while for technical reasons. Maybe they'll become popular again if SACD really takes hold. A situation with a certain wry irony for Bob Stuart if it occurs... ;- Slainte, Jim -- Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm Audio Misc http://www.st-and.demon.co.uk/AudioMisc/index.html Armstrong Audio http://www.st-and.demon.co.uk/Audio/armstrong.html Barbirolli Soc. http://www.st-and.demon.co.uk/JBSoc/JBSoc.html |
#11
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System warm-up
Jim Lesurf wrote:
In article , Tat Chan wrote: James Harris wrote: Nad C541i as transport, Meridian 203 DAC, Rotel RA-02 amp, Dynaudio Audience 62 floorstand speakers James, I am curious. The Meridian DAC is at least 12 years old. I would have thought that the newer Burr Brown DACs in the NAD would measure better and produce "better" sound than the older Philips DAC in the Meridian (is it multibit or bitstream?) I doubt that this is simply a matter of choice of DAC chip. Other influences will include the PSU, buffering, differences in filtering, etc. well yes, but the NAD 541i is a one box solution and as such, shouldn't it have much lower jitter levels compared to using a separate DAC and transport, even with the well-engineered Meridian DAC? And since the NAD player has HDCD playback capability, it must use a certain digital filter that is highly regarded? (can't remember the name of it atm) FWIW I remain a fan of the Meridian 263 and 563, (as well as the Quad 67) despite them being 'out of favour' for a while for technical reasons. what would the technical reasons be? Did they process/filter the digital data in a "funny" way? Maybe they'll become popular again if SACD really takes hold. A situation with a certain wry irony for Bob Stuart if it occurs... ;- and why would that be? (possibly related to my question above) |
#12
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System warm-up
Tat Chan wrote:
James, I am curious. The Meridian DAC is at least 12 years old. I would have thought that the newer Burr Brown DACs in the NAD would measure better and produce "better" sound than the older Philips DAC in the Meridian (is it multibit or bitstream?) As old as the 203 is, there's a good chance that a $39.95 Apex DVD player has better-performing DACs. Seriously. |
#13
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System warm-up
Arny Krueger wrote:
Tat Chan wrote: James, I am curious. The Meridian DAC is at least 12 years old. I would have thought that the newer Burr Brown DACs in the NAD would measure better and produce "better" sound than the older Philips DAC in the Meridian (is it multibit or bitstream?) As old as the 203 is, there's a good chance that a $39.95 Apex DVD player has better-performing DACs. Seriously. OK, the DAC in the newer elcheapo DVD player might be better performing, but I doubt the analogue output stage would be better than the Meridian's (granted, I am moving the goalposts here, since I have now changed the point from DAC to output stage) |
#14
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System warm-up
"Tat Chan" wrote in message ... snip Nad C541i as transport, Meridian 203 DAC, Rotel RA-02 amp, Dynaudio Audience 62 floorstand speakers James, I am curious. The Meridian DAC is at least 12 years old. I would have thought that the newer Burr Brown DACs in the NAD would measure better and produce "better" sound than the older Philips DAC in the Meridian (is it multibit or bitstream?) Well, since you asked I tried going back to the direct link from the CD player to the amp. I soon went back to the DAC. The reason? I wouldn't like to say the DAC is "better" but is a sound I prefer. The DAC gives greater bass weight and authority and also opens out the voices. They sound more clear and distinct with the DAC than with the Nad CD player alone. I would still like more reach in the bass, though. That may be to do with my speakers more than the electronics. -- Cheers, James |
#15
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System warm-up
James Harris wrote:
"Tat Chan" wrote in message ... snip James, I am curious. The Meridian DAC is at least 12 years old. I would have thought that the newer Burr Brown DACs in the NAD would measure better and produce "better" sound than the older Philips DAC in the Meridian (is it multibit or bitstream?) Well, since you asked I tried going back to the direct link from the CD player to the amp. I soon went back to the DAC. The reason? I wouldn't like to say the DAC is "better" but is a sound I prefer. The DAC gives greater bass weight and authority and also opens out the voices. They sound more clear and distinct with the DAC than with the Nad CD player alone. Interesting. I was thinking of getting a 203 DAC, as the shop I bought my speakers from have one for sale, but the £160 they are charging seems a bit steep. I would still like more reach in the bass, though. That may be to do with my speakers more than the electronics. well, your floorstanders will produce more bass than my bookshelves! |
#16
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System warm-up
"James Harris" no.email.please wrote in message .. . "Tat Chan" wrote in message ... snip Nad C541i as transport, Meridian 203 DAC, Rotel RA-02 amp, Dynaudio Audience 62 floorstand speakers James, I am curious. The Meridian DAC is at least 12 years old. I would have thought that the newer Burr Brown DACs in the NAD would measure better and produce "better" sound than the older Philips DAC in the Meridian (is it multibit or bitstream?) Well, since you asked I tried going back to the direct link from the CD player to the amp. I soon went back to the DAC. The reason? I wouldn't like to say the DAC is "better" but is a sound I prefer. The DAC gives greater bass weight and authority and also opens out the voices. They sound more clear and distinct with the DAC than with the Nad CD player alone. I would still like more reach in the bass, though. That may be to do with my speakers more than the electronics. Have since added a borrowed Quad 405 power amp. While this has removed the warm-up time needed before I still would like greater reach in the bass - and probably a little less of it! I think then that this must be to do with my Dynaudio speakers. The cones in them are probably too small to reach as far down as I would like. Oh well. The neighbours can breathe a sigh of relief.... -- James |
#17
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System warm-up
In article , James Harris
no.email.please wrote: "S888Wheel" wrote in message ... snip My hi-fi sounds great sometimes and not others. snip Maybe you could give us the specifics on your system. Nad C541i as transport, Meridian 203 DAC, Rotel RA-02 amp, Dynaudio Audience 62 floorstand speakers Chord Optichord digital link, Audioquest Python interconnects, Atlas 2.0 speaker cable, Atacama Equinox rack Since this is being cross-posted to 'opinion'... :-) FWIW I use two main systems. One now uses a pair of ESL63's and a Meridian 263 DAC. The other now uses a pair of ESL988's and a Meridian 563 DAC. (You may spot a pattern, here... ;- ) In each case I tend to switch the speaker energisation and DAC power on in the morning, and off at the end of the evening. I have a slight impression that the speakers (and maybe the DACs) benefit from this. However the changes are so small I am not at all sure of this. I general I don't bother switching on amplifiers more than a few mins before use. So far as I can tell, letting my amplifiers warm up has no effect that seems audible to me. The dealer advised a 30 to 60 minute warmup before each listening session - which is a pain and I'm not convinced that the improved sound quality follows such a warmup. The improvement seems random - and unexpected. Maybe mains problems? The sonic difference to the bass is quite clear. Forgive the adjectives but when it's not working well the sound is OK but 'thin' and lacks energy. When it works well the bass is rich and the sound fuller and more musical at the same volume. It even sounds good with the volume lower. The Audioquest Pythons were the last addition. I wasn't happy with the system - it didn't have the clarity - until they were added to replace Atlas Voyagers. Does the kit list above give any clues as to why the sound would change? (BTW, thanks too for your suggestions on test CDs.) I also hear (apparent) changes from time to time in terms of relative bass level, etc. However it does not seem to correlate with anything so I suspect it is just my perceptions altering as a result of various 'extraneous' influences... Slainte, Jim -- Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm Audio Misc http://www.st-and.demon.co.uk/AudioMisc/index.html Armstrong Audio http://www.st-and.demon.co.uk/Audio/armstrong.html Barbirolli Soc. http://www.st-and.demon.co.uk/JBSoc/JBSoc.html |
#18
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System warm-up
On Fri, 16 Apr 2004 11:43:39 +0100, Jim Lesurf
wrote: In each case I tend to switch the speaker energisation and DAC power on in the morning, and off at the end of the evening. I have a slight impression that the speakers (and maybe the DACs) benefit from this. The manual for the Quad '57 speakers recommends leaving them powered all the time and not switching them off. Is the advice given for the '63/988/989 different? My Stax electrostatic headphones sound noticeably 'edgy' for the first few minutes after switch-on. I have not investigated this in any detail, but it seems reasonable that high-impedance capacitive systems will need a little time to stabilise because there may be some fairly long time constants associated with the biasing supply. This would tie in with the instructions Quad provide for monitoring the HT bias supplies of the '57 in which they specify the use of an electrostatic volt meter because the input impedance of a standard meter is sufficiently low to affect the reading. (Of course in those days, the majority of meters were not electronic.) -- Chris Isbell Southampton UK |
#19
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System warm-up
In article , Chris Isbell
writes On Fri, 16 Apr 2004 11:43:39 +0100, Jim Lesurf wrote: In each case I tend to switch the speaker energisation and DAC power on in the morning, and off at the end of the evening. I have a slight impression that the speakers (and maybe the DACs) benefit from this. The manual for the Quad '57 speakers recommends leaving them powered all the time and not switching them off. Is the advice given for the '63/988/989 different? Leave mine on all the time, doesn't seem to harm them. Better than not remembering to switch them on as other members of the tribe here use them and would forget!.... -- Tony Sayer |
#20
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System warm-up
In article , Chris Isbell
wrote: On Fri, 16 Apr 2004 11:43:39 +0100, Jim Lesurf wrote: In each case I tend to switch the speaker energisation and DAC power on in the morning, and off at the end of the evening. I have a slight impression that the speakers (and maybe the DACs) benefit from this. The manual for the Quad '57 speakers recommends leaving them powered all the time and not switching them off. Is the advice given for the '63/988/989 different? I don't have the 63 booklet to hand. My recollection is that it also recommends leaving the mains 'on' all the time. Looking at the blue one for the 988's I can't find a mention of this, though. Ideally, I'd leave them powered all the time. However I tend to be wary of leaving items on overnight due to the very slight risk of fire. My Stax electrostatic headphones sound noticeably 'edgy' for the first few minutes after switch-on. I have not investigated this in any detail, but it seems reasonable that high-impedance capacitive systems will need a little time to stabilise because there may be some fairly long time constants associated with the biasing supply. My impression is that the speakers do improve over a few hours of being 'on'. However this may be my ears, of course, not the speakers. :-) On one occasion I was away for a week and left the 63's unpowered. I cam home and started listening to music. It was only after about ten minutes that I realised that I'd set the volume about 6dB higher than usual, and that the sound was 'not quite right'. I hadn't turned on the energisation. :-) This shows that they do sometimes keep a surprisingly high charge for a long time. IIRC the 57's would not hold charge like this, though. I'm not sure, but suspect the problem may be that the charge distribution (rather than amount) needs to 'settle' and this takes times as the diaphragm is actually quite resistive. Also any moisture may need to be 'ionised away' by leakage. This might be a reason for allowing the speakers to be powered for a long time. Slainte, Jim -- Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm Audio Misc http://www.st-and.demon.co.uk/AudioMisc/index.html Armstrong Audio http://www.st-and.demon.co.uk/Audio/armstrong.html Barbirolli Soc. http://www.st-and.demon.co.uk/JBSoc/JBSoc.html |
#21
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System warm-up
"James Harris" no.email.please wrote in message .. . "S888Wheel" wrote in message ... snip My hi-fi sounds great sometimes and not others. snip Maybe you could give us the specifics on your system. Nad C541i as transport, Meridian 203 DAC, Rotel RA-02 amp, Dynaudio Audience 62 floorstand speakers Chord Optichord digital link, Audioquest Python interconnects, Atlas 2.0 speaker cable, Atacama Equinox rack The dealer advised a 30 to 60 minute warmup before each listening session - which is a pain and I'm not convinced that the improved sound quality follows such a warmup. The improvement seems random - and unexpected. Maybe mains problems? The sonic difference to the bass is quite clear. Forgive the adjectives but when it's not working well the sound is OK but 'thin' and lacks energy. When it works well the bass is rich and the sound fuller and more musical at the same volume. It even sounds good with the volume lower. The Audioquest Pythons were the last addition. I wasn't happy with the system - it didn't have the clarity - until they were added to replace Atlas Voyagers. Does the kit list above give any clues as to why the sound would change? (BTW, thanks too for your suggestions on test CDs.) A followup on this. I have since been kindly lent a Quad 405 power amp. With this the system does NOT need a warm up. As before the kit is left on all the time. -- James |
#22
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System warm-up
James, any comment about the Atacama Equinox rack? Is it the Av, HiFi, or XL
Pro? I am about to buy one of these, are you happy with it? -- "James Harris" no.email.please a écrit dans le message de ... "James Harris" no.email.please wrote in message .. . "S888Wheel" wrote in message ... snip My hi-fi sounds great sometimes and not others. snip Maybe you could give us the specifics on your system. Nad C541i as transport, Meridian 203 DAC, Rotel RA-02 amp, Dynaudio Audience 62 floorstand speakers Chord Optichord digital link, Audioquest Python interconnects, Atlas 2.0 speaker cable, Atacama Equinox rack The dealer advised a 30 to 60 minute warmup before each listening session - which is a pain and I'm not convinced that the improved sound quality follows such a warmup. The improvement seems random - and unexpected. Maybe mains problems? The sonic difference to the bass is quite clear. Forgive the adjectives but when it's not working well the sound is OK but 'thin' and lacks energy. When it works well the bass is rich and the sound fuller and more musical at the same volume. It even sounds good with the volume lower. The Audioquest Pythons were the last addition. I wasn't happy with the system - it didn't have the clarity - until they were added to replace Atlas Voyagers. Does the kit list above give any clues as to why the sound would change? (BTW, thanks too for your suggestions on test CDs.) A followup on this. I have since been kindly lent a Quad 405 power amp. With this the system does NOT need a warm up. As before the kit is left on all the time. -- James |
#23
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"Frédéric Mathieu" wrote in message ... James, any comment about the Atacama Equinox rack? Is it the Av, HiFi, or XL Pro? I am about to buy one of these, are you happy with it? I bought the Equinox audio rack. I guess it would be the HiFi one you mention. I can't really comment on this compared with other racks as I didn't try any others. I do find the rack to be solid with my base unit plus two extra shelves - four in total. The triangular design (of the pillars and feet) is convenient. Watch out, though, for its depth. It sticks out further in to my room than I would like. There is certainly plenty of room for deep units! Compared with the old wooden rack and stacked components I had before placing the amp in space on its own shelf even improved the sound from the tuner. No, really! The sound just seemed to open out and breathe more freely. I still find this hard to believe. One day I'll go back to stacked units just to convince myself....... -- HTH, James |
#24
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System warm-up
"James Harris" no.email.please wrote in message .. . Hi, My hi-fi sounds great sometimes and not others. I am told that it needs an hour's warm-up and this could fit with the times it has sounded good. For example, great one evening but poor the next morning. I leave the electronics on but not playing. Is there a CD that can be played to loosen the system up? I suspect the speakers most. Bass extension is particularly absent at times. Any suggestions as to whether playing a very low frequency sine wave or similar could do the trick? -- TIA, James My hi-fi sounds great late night and during the early hours... single malt may have a lot to do with it ;-) |
#25
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"Mike Gilmour" wrote
My hi-fi sounds great late night and during the early hours... single malt may have a lot to do with it ;-) Beer googles for the ears? Martin -- M.A.Poyser Tel.: 07967 110890 Manchester, U.K. http://www.fleetie.demon.co.uk |
#26
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#27
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"Fleetie" wrote in message ...
"Mike Gilmour" wrote My hi-fi sounds great late night and during the early hours... single malt may have a lot to do with it ;-) Beer googles for the ears? Martin My ears google for free beer :-) |
#28
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#29
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System warm-up
"James Harris" wrote My hi-fi sounds great sometimes and not others. I am told that it needs an hour's warm-up and this could fit with the times it has sounded good. For example, great one evening but poor the next morning. I leave the electronics on but not playing. Perhaps you might consider a power line conditioner. These devices reduce RF, EMI and other distortions that leak into your hi-fi gear from AC power lines. While some equipment does not appear (sound wise) to benefit from the device most will, IME. Most audio stores will allow you to demo these devices for free so there is no financial risk. The cost of these units start at $200 and run up to $4,000 depending on your needs. For a periodical review of these units check out Stereophile issue Vol. 17 No. 12. Is there a CD that can be played to loosen the system up? I suspect the speakers most. Bass extension is particularly absent at times. Any suggestions as to whether playing a very low frequency sine wave or similar could do the trick? Yes, they are commonly referred to as break-in or system burn-in CD’s. They range from highly specialized (Purest Audio Design System Enhancer, $110) to a single track on a test CD (Cardas/Ayre System Enhancement Disk, $20 or XLO/Reference Recordings Test and Burn-In CD, $27). |
#30
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In article ,
Powell wrote: Most audio stores will allow you to demo these devices for free so there is no financial risk. The cost of these units start at $200 and run up to $4,000 depending on your needs. For a few chokes and capacitors at most? Some people have more money than sense. Better to buy equipment where the maker has catered for possible mains borne interference. For a periodical review of these units check out Stereophile issue Vol. 17 No. 12. Love to know how you arrange for a 'dirty' mains supply to be anything like typical. -- *Eat well, stay fit, die anyway Dave Plowman London SW 12 RIP Acorn |
#31
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"Dave Plowman" wrote Most audio stores will allow you to demo these devices for free so there is no financial risk. The cost of these units start at $200 and run up to $4,000 depending on your needs. For a few chokes and capacitors at most? For example, better designs might include having isolated transformers, balanced design technology, regeneration of the wave form, outlet isolation/open ground, provide for special need of source/power amps just to prevent electrical grid injection noise. Some people have more money than sense. Better to buy equipment where the maker has catered for possible mains borne interference. And, some people have bad credit (no plastic) which prevents them from trying a free demo unit in their home setup. Or they don’t know any better. Which are you? For a periodical review of these units check out Stereophile issue Vol. 17 No. 12. Love to know how you arrange for a 'dirty' mains supply to be anything like typical. Consider doing your own home work (empirical experience). |
#32
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"Powell" wrote in message ... "Dave Plowman" wrote Most audio stores will allow you to demo these devices for free so there is no financial risk. The cost of these units start at $200 and run up to $4,000 depending on your needs. For a few chokes and capacitors at most? For example, better designs might include having isolated transformers, balanced design technology, regeneration of the wave form, outlet isolation/open ground, provide for special need of source/power amps just to prevent electrical grid injection noise. Some people have more money than sense. Better to buy equipment where the maker has catered for possible mains borne interference. And, some people have bad credit (no plastic) which prevents them from trying a free demo unit in their home setup. Or they don’t know any better. Which are you? For a periodical review of these units check out Stereophile issue Vol. 17 No. 12. Love to know how you arrange for a 'dirty' mains supply to be anything like typical. Consider doing your own home work (empirical experience). Note to UK readers - they're not all locked up yet! |
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In article ,
Powell wrote: For a few chokes and capacitors at most? For example, better designs might include having isolated transformers, balanced design technology, regeneration of the wave form, outlet isolation/open ground, provide for special need of source/power amps just to prevent electrical grid injection noise. You must be referring to US stuff. All UK equipment already has an isolating transformer. It would be illegal to sell one without. Some people have more money than sense. Better to buy equipment where the maker has catered for possible mains borne interference. And, some people have bad credit (no plastic) which prevents them from trying a free demo unit in their home setup. Or they dont know any better. Which are you? I know that you're advocating the spending of money that isn't needed. Just buy decent equipment in the first place. For a periodical review of these units check out Stereophile issue Vol. 17 No. 12. Love to know how you arrange for a 'dirty' mains supply to be anything like typical. Consider doing your own home work (empirical experience). So I take it you just do 'subjective' testing then? Figures. -- *Change is inevitable ... except from vending machines * Dave Plowman London SW 12 RIP Acorn |
#34
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"Dave Plowman" wrote For a few chokes and capacitors at most? For example, better designs might include having isolated transformers, balanced design technology, regeneration of the wave form, outlet isolation/open ground, provide for special need of source/power amps just to prevent electrical grid injection noise. You must be referring to US stuff. All UK equipment already has an isolating transformer. It would be illegal to sell one without. Please re-read the above paragraph. It’s “transformers”... that means plural in English. plural adjective 1 more than one in number. 2 Grammar (of a word or form) denoting more than one. Here’s and example of the of the design I use. http://www.audiopower.com/newsite/toc.html Some people have more money than sense. Better to buy equipment where the maker has catered for possible mains borne interference. And, some people have bad credit (no plastic) which prevents them from trying a free demo unit in their home setup. Or they dont know any better. Which are you? I know that you're advocating the spending of money that isn't needed. How would you know? Just buy decent equipment in the first place. Quack, quack, quack... For a periodical review of these units check out Stereophile issue Vol. 17 No. 12. Love to know how you arrange for a 'dirty' mains supply to be anything like typical. Consider doing your own home work (empirical experience). So I take it you just do 'subjective' testing then? Figures. Sure, you can demo one and find out for yourself.... depending on your financial limitations. For your edification, Mr. Plowman: Nigel's Power Line Conditioner Info Sheet (C) 2000 V 1.15 This document may be copied so long as it is copied in it's entirety, including copyright, and so long as it is not posted to rec.audio.high-end Sections: I. What IS a Power Line Conditioner? II. Why do I NEED/WANT one? III. HTML Links IV. Specific Products & Technology V. Cheap Tweaks for the Dangerously Inclined VI. Closing Comments I. What IS a Power Line Conditioner? ===================================== Before there was such a market for high end tweaks and buzz words in high end audio/video companies like APCC & Tripplite among many others were already making power conditioners for the computer and electronics industry. These devices are still made and they are used to provide voltage regulation for devices like copiers. They used transformers with multiple taps, and as the input voltage surges or sags the relays or transistors in the power conditioner would switch among the different transformer taps. I thought Tice or Audio Power made a similar device, but I seem to be mistaken. Two good sources of non- esoteric power line conditioners are www.furmasound.com and www.equitech.com. Pretty good looking stuff if you have common surge/sagging problems. Today there are many things called a line conditioner, and they are not all the same. In general a power line conditioner can be everything from a power strip with surge protection to larger, beefy boxes that do a variety of things to the incoming AC power. A line conditioner may have some features to do the following: 1. Filter the AC signal so you get closer to an ideal 60 Hz signal. 2. Provide surge protection 3. Provide Under / Over voltage protection (turns off) 4. Provide Under / Over voltage regulation (keeps the output voltage constant) 5. Provide power outage protection (like an Uninterruptable Power Supply) 6. Provide a lower apparent impedance to the source (like PS Audio, Elgar, etc.) Different products work differently, and will have different feature mixes. The heavier, the more you are paying for, so beleive it or not the cost per pound is a good indicator of how much is going into the product, and a good guage of how much you should be paying for it. If you just spent $1,300 on a power strip you can pick up with your pinky, you paid too much. Articles in Hi Fi News and Record Review (a brit mag) in 1998-99 give some insight into building your own. Alas not all filtration is the same. Products which claim to filter RFI/EMI only start to work at around 100 kHz or higher, which is far above human audibility. The theoretically ideal power line filter would filter out all signals below and above 60 Hz. II. Why do I NEED/WANT one? ============================ II.a: NEEDS Unless you suffer from chronic over/under voltages at your house then chances are you don't really need a power conditioner, the system will work reliably without it. You may very well find that surge protection is important to you. Check out the separate "Nigel's Surge Supression Info Sheet". If you're buying some fancy power line conditioner that is supposed to include surge protection, ask them if the equipment has been certified to UL 1449 Second Edition. I have yet to see an audio equipment "Conditioner" manufacturer that claims surge supression publish any sort of UL or CSA listing on their web site, so be careful about relying on them for surge supression. This does not include Monster Cable's strips, they are primarily a surge supressor, with noise filters added, and are in fact UL 1449 certified. II.b: WANTS Audio/videophiles WANT power conditioners because they feel it will improve the quality of their listening or viewing experience. How much of an audible or visible difference a power line conditioner will make in your world depends on the following: 1. The quality of your incoming AC power. 2. The quality of your components power supplies. 3. The resolution of your system (Fix your room acoustics first, then worry about power line issues) 4. The effectiveness & features of the line conditioner. 5. How much noise the line conditioner itself actually creates (a potential problem in a UPS) 6. What frequencies the power conditioner's filtration is effective at. 7. Your gullibility An example of exceptional power supply design is found in much of Krell and Mark Levinson equipment some of which use fully regulated, fully balanced power supplies. This is a rare thing, but any potential benefit from a power conditioner may be a mute point with this equipment. Most amplifiers use unregulated, but highly filtered power supplies, relying on the incoming AC voltage remaining constant, and large capacitors to reduce any noise on the line. II.c: WON'Ts One thing most line conditioners don't do is fix ground loop problems (i.e. a loud 60 Hz hum you hear coming from your speakers), in some cases they can actually make things worse by improving the connection to ground of your equipment. The ideal way to fix a ground loop problem is to use signal level isolation transformers between your system and the source of the problem, which is often the cable TV or a computer connection. Check out: www.jensentransformers.com for a variety of safe solutions. Otherwise, if you want to start a fire or electrocute yourself or your family, use a 2-3 prong adaptor, a.k.a. a cheater plug. There is one exception to this. Power conditioners that provide balanced outputs may reduce ground loop related hums, as well as provide a good lowering of the overall noise floor. Also, power conditioners should not be used to substitute for bad electrical wiring. In some cases a power conditioner may make things worse, drawing more current and stressing the existing wiring. You should NEVER over fuse wiring. III. HTML Links ================ Here is a variety of links to people selling things that go between your equipment and the incoming AC line. www.apcc.com www.audiopower.com www.accuphase.com www.belkin.com www.bestpower.com www.brickwall.com www.elgar.com www.equitech.com www.furmasound.com www.monstercable.com www.psaudio.com www.surgex.com www.ticeaudio.com www.tripplite.com www.vansevers.com You should also check the links from www.stereophile.com which seem to be pretty exhaustive, and mention many more manufacturer links to audio related power line products than I do here. Be warned however that while the list at Stereophile may be more comprehensive than mine, it's less discriminating, and includes some products I feel provide particularly poor return on investment. IV. Products & Technology ========================== Some products merit special attention in my book, for a variety of reasons. Monster Cable ============= Despite having the WORST web site in all of audio regarding technology, with gross technical and gramatical errors, several people have sent me e-mails defending their power strips, claiming they made improvements in picture or video quality. Heck if I know, but you might want to, they're not too expensive. Panamax ======= Panamax gets special because they do have complete A/V surge protection solutions their parts quality does not usually merit what they charge, like $99 for a standard surge strip, and I've read of reliability and warranty problems online, so you should check the archives at www.deja.com. In my opinion APCC, Triplite and Belkin all give you more surge protection/dollar than Panamax. The Panamax DBS+ I have (got a deal on it) has failed to protect my two satelite receivers from wind related static discharge , so I'm not too happy with them these dayas. Brickwall & Zerosurge ===================== Working on a completely different principle of surge protection than MOV based surge protectors are the models from Brick Wall and ZeroSurge. They are basically single pole low pass filters ( a good thing ) for your power lines. The claimed response is -3db at 3 kHz. This effectively limits the maximum Volts/Second. When a surge hits, it becomes a 2nd and 3rd order low pass filter. Surgex also OEM's these devices, or licenses the technology. This low start point for their noise filtration puts them into both my Line Conditioner sheet as well as my Surge Protection sheet. Audo Power & Tice ================= Moving closer to the ideal of a power line conditioner are the ones that use isolation transformers. These have a much better capacity to remove audible power line noise than mere surge strips. Audio Power & Tice have a variety of products you should take a listen to, if you can get past Tice's voodoo web pages (i.e. their Q&A section). Note that not all these products use isolation transformers, so check to be sure what you're getting. Richard Gray's Power Company ============================ Tremendous hype on their web site is parroted almost word for word by dealers and customers. Their web site and "Grey Paper" fails to make any truly technical statements about what the product does and IMHO they offer poor return on investment, considering the parts that actually go into them, and that they sell for around $700. I would encourage people to either spend another $300 for a PS Audio unit, or spend less for something from Furmasound or Equitech, or even getting a power conditioner (not a UPS) from APC or Tripp Lite instead of buying a product from this company. PS Audio ======== New are the Power Plant models from PS Audio. PS Audio has taken the high road, and said electrical bill be damned! We'll get clean power no matter the cost. The Power Plant models are basically power amplifiers that re-create the 115 Volt AC signal at their output. They are perhaps the most ambitious designs I've seen so far and again have some good ideas behind them. Their prices seem very reasonable, considering how much goes into one and the current offerings of power conditioners in the market, and they certainly should be able to meet their twin goals of: Greatly reducing apparent power line impedance - AND - Greatly reducing power line noise and distortion The technology used may very well be the best at doing those two things in combination. Since the Power Plants are essentially class AB amplifiers they are no better than 50% efficient, so expect it to add additional heat and electrical current draw to your electric circuit, which is something to pay attention to if you're close to being overloading it already. On the other hand, using a linear (AB) amplifier stage removes the likelihood of more digital noise being introduced into the 60 Hz waveform it generates. If the PS Audio units don't have enough current capacity, consider the products from Elgar, sweeet....way expensive! If you have money to burn, perhaps you should consider an Elgar as a pre-conditioner, and use a PS Audio unit for your source components only. Other equipment manufacturers should also take note that unlike many sites PS Audio's web site was delightfully free of bovine scatalogical samples. Chang Lightspeed ================ Chang Lightspeed need comments on because of their on-line advertising which demonizes coils & transformers. They're right about small, poorly designed coils actually increasing the power line impedance, however what they fail to note is that by going coilless their conditioners may very well not be able to remove any power line noise within the audible spectrum. This noise is the most important to audiophiles are concerned with as it has the best chance of being propagated through the power supplies of the equipment and finally to our ears. Perhaps this is why their on-line advertising mentions RFI/EMI noise reduction so much, and makes no mention of audio frequency noise reduction. Coil impedance can be overcome by using bigger and better inductors. Does anyone know how much these puppies weigh? I bet you they're lighter and are less expensive to manufacture than comparative products from manufacturers who DO use coils in their designs. Uninterruptable Power Supplies ============================== A UPS is a must for anyone doing serious computer work, but it's benefits for audiophiles will vary. If you're going to try a UPS to improve the sound / picture quality then avoid the standby kind, which have a 2-4 ms lag before they turn on. Get one labeled "line interactive." Because UPS's are designed for computers they usually pay little attention to how much grunge is coming out when they generate the output waveform, which could in turn easily make your system sound worse, not better. The solution is to make sure the output of your UPS is a sine wave, with the lowest possible distortion and noise. So, avoid "stepped aproximation" and look for "pure sinewave" output. Lastly, most UPS have a relatively loose voltage regulation. For example, as the input voltage varies from 90 to 145 volts the UPS will output from 105 to 125 volts. It's a smaller variation than what's coming in, and it's certainly better than any passive conditioners like Audio Power or Tice but it's certainly not the best technology could do if money were no object. Radio Shack =========== Yes, RS can be an audiophiles best friend, especially when he/she is looking for a $20 voltage meter. If you think you have a chronic voltage problem at your home or listening room outlets go get a meter and find out. If it's bad enough, perhaps you should start with a phone call to your electrical company and/or electrician before getting a voltage conditioner. V. Cheap Tweaks for the Dangerously Inclined ============================================= One potential improvement audiophiles can make, fairly easily if they are electronically and dangerously inclined, is to increase the power supply filter capacitance. You can do this both by replacing the current storage capacitors to higher values of capacitance (and equal or better voltages) and also by adding storage capacitance across the maximum + and - voltage rails of the device (make sure the capacitor's voltage rating is greater than the difference between the + and - rails, of course). While we're going there, consider also replacing the filter caps with less inductive versions if possible such as caps from Sanyo or Panasonic (I think, sorry, it's been a while since I was opening data books so check this out yourself) as well as adding polypropelyne or polystyrene capacitors of equal or greater voltage rating in parallel with any upgrades you do. Be careful with how much capacitance you add, adding capacitance increases the turn on (inrush) current and may over-stress the bridge rectifier. Of course, the fix for this is to add a bigger rectifier so you can get more power! (Grunt grunt!) And if you fry your transforer too, well that can be fixed as well! This little tweak alone can greatly increase the S/N ratio of many mass market electronic devices far more than other tweaks, such as new power cables. If you already have a very good power supply it won't matter much as if you didn't (i.e. it will make a bigger difference for mass market Sony or Yamaha than Krell or Mark Levinson). I won't go into any more detail than this, if you have to ask chances are you shouldn't be in there anyway. Oh, yeah, and as always, if you're an idiot and hurt yourself or your equipment don't call me, have your mama call me so I can tell her what a dufus you are. VI. Closing Comments ===================== I don't mean to exclude anyone, so if I missed you or a product you feel deserves special mention send an e-mail to nigel_tufnel@my- deja.com and I'll add it onto this growing and improving list. As always, thoughtful, informative discussions are encouraged, corrections are gladly accepted, and flames may be sent to . It's your ears, eyes and wallet you're trying to please. Advice from anyone is a good way to start but it's your hard earned dollar so you should always be the final judge of a products worth. |
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On Wed, 14 Apr 2004 17:22:56 +0100, Dave Plowman
wrote: In article , Powell wrote: Most audio stores will allow you to demo these devices for free so there is no financial risk. The cost of these units start at $200 and run up to $4,000 depending on your needs. For a few chokes and capacitors at most? Some people have more money than sense. Better to buy equipment where the maker has catered for possible mains borne interference. Quite so. Anything with a CE mark has to adhere to pretty rigid standards for protection against EMI susceptibility. For a periodical review of these units check out Stereophile issue Vol. 17 No. 12. Love to know how you arrange for a 'dirty' mains supply to be anything like typical. Live in an apartment block next to a welding shop? :-) -- Stewart Pinkerton | Music is Art - Audio is Engineering |
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"Stewart Pinkerton" wrote in message ... On Wed, 14 Apr 2004 17:22:56 +0100, Dave Plowman wrote: In article , Powell wrote: Most audio stores will allow you to demo these devices for free so there is no financial risk. The cost of these units start at $200 and run up to $4,000 depending on your needs. For a few chokes and capacitors at most? Some people have more money than sense. Better to buy equipment where the maker has catered for possible mains borne interference. Quite so. Anything with a CE mark has to adhere to pretty rigid standards for protection against EMI susceptibility. For a periodical review of these units check out Stereophile issue Vol. 17 No. 12. Love to know how you arrange for a 'dirty' mains supply to be anything like typical. Live in an apartment block next to a welding shop? :-) -- Stewart Pinkerton | Music is Art - Audio is Engineering Now that would be really unfortunate! What constitutes 'dirty' mains anyway? What about utilities signalling systems, mains borne baby alarms, intercom systems etc, not as invasive as Stewarts suggestion of a neighbouring welding shop but pollution never the less. I'm way out the in country but 'scoping my mains showed evenly spaced spikes... tracked down to an electric fence a third of a mile away. ;-) Mike |
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In article ,
Mike Gilmour wrote: What constitutes 'dirty' mains anyway? What about utilities signalling systems, mains borne baby alarms, intercom systems etc, not as invasive as Stewarts suggestion of a neighbouring welding shop but pollution never the less. I'm way out the in country but 'scoping my mains showed evenly spaced spikes... tracked down to an electric fence a third of a mile away. ;-) A well designed mains transformer will attenuate anything outside about 50 Hz by a considerable amount - if it didn't, decent audio transformers wouldn't be so expensive. ;-) Here in London, the mains is anything but a pure sine wave - I'd guess because of all the SWPS around. -- *Don't worry; it only seems kinky the first time.* Dave Plowman London SW 12 RIP Acorn |
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"James Harris" no.email.please wrote:
Hi, My hi-fi sounds great sometimes and not others. I am told that it needs an hour's warm-up and this could fit with the times it has sounded good. For example, great one evening but poor the next morning. I leave the electronics on but not playing. Is there a CD that can be played to loosen the system up? I suspect the speakers most. Bass extension is particularly absent at times. Any suggestions as to whether playing a very low frequency sine wave or similar could do the trick? Hi-fi loudspeakers are well known to change after playing some time as the voice coil heats up. If you can hear the difference perhaps it is time to invest in some monitor speakers instead. They tend to use heavier gauge voice coil windings and are better at removing heat from them too. Ian Ian |
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