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#81
Posted to rec.audio.pro
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USB hum/noise isolation?
On Mar 24, 11:10 am, wrote:
On Mar 20, 2:07 pm, "Arny Krueger" wrote: "StudioDog" wrote in message roups.com And does that happen with both the Behringer interface and the Alesis used as output device? Meindert Yes. The noise comes through either interface as soon as I boot Cubase. Nothing attched to the interface but the computer? I have the same problem. I run Reason 3.0 and Cubase SX3, an Alesis Multimix8, and an EMU Xboard 61 USB controller. As soon as I boot up either program-- seperately or using ReWire-- the hum starts with nothing connected to the inputs. Here is the interesting bit. If I play with the sample rate in Reason the pitch of the sound changes. If I play with theASIO buffer size in the driver (ASIO4all) the hum becomes more modulated as the buffer size gets larger (i.e. the hum begins to pulse). When I listen to music through the Alesis using iTunes the hum is not there. StudioDog, does any of this reflect your experience? This suggests a problem with the mixer's USB data input-- maybe a bad D to A conversion on the input stage? John - your symptoms seem too much like mine to be a separate problem! I haven't played with buffer settings too much, as I figured if the noise was present in both of my usb interfaces (Alesis multimix8 and Behringer UCA202) the trouble was systemic. Up til your post I thought I was the only one experiencing this! Now at least I know I'm not totally crazy! I don't know enough a out the techie side of USB to guess where the problem might lie, but I think it's safe to say that there IS a real issue here! As I can't currently afford to buy a more expensive interface, I'm going to try cutting the noise out of my monitor path with a transformer isolation box between the interface (behringer unit) and the mixer Tape In's (try as I might, I can't find any affordable product that will isolate the USB line itself, so I'm bypassing the Alesis usb port altogether). I've got an ART DTI dual transformer isolation box on order from my local shop - I'll let you know if it does the trick! Like Red Green says, "We're all in this together!" |
#82
Posted to rec.audio.pro
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USB hum/noise isolation?
Here is the interesting bit. If I play with the sample rate in Reason the pitch of the sound changes. If I play with theASIO buffer size in the driver (ASIO4all) the hum becomes more modulated as the buffer size gets larger (i.e. the hum begins to pulse). When I listen to music through the Alesis using iTunes the hum is not there. I'm not sure if the problem is inherent in USB (at least the cheap interfaces in the Alesis, Behringers, etc), or in the ASIO drivers, or a bit of both. I keep looking for newer/better Asio drivers, but they all carry this beeping/pulsing noise for me so far. the Alesis deck, mine is also quiet as a mouse when not using the usb/asio drivers. I used it at a live St Paddy's show for 5 hours with nary a problem. I have not tries it hooked to the analogue inputs of my computer's cound card, though. That may be next, although I really don't want the hassle of adapters/cables and impedence matching to run TRS cables from the deck to the 1/8" input on the computer! |
#83
Posted to rec.audio.pro
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USB hum/noise isolation?
"StudioDog" wrote ...
the Alesis deck, mine is also quiet as a mouse when not using the usb/asio drivers. Or perhaps you just can't hear the noisy digitized signal when not using the drivers required to access it. "Daddy, can you see me when my eyes are closed?" It seems highly unlikely that this has anything to do with software. |
#84
Posted to rec.audio.pro
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USB hum/noise isolation?
On Mar 24, 9:37 pm, "Richard Crowley" wrote:
It seems highly unlikely that this has anything to do with software. So your opinion would be that the glitch lies in the A/D/A converters in the interface? |
#85
Posted to rec.audio.pro
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USB hum/noise isolation?
wrote in message
ups.com... I'd like to put up my hand at this time to say I've been experiencing the same annoying problem with My Nehringher xenyx 1622 mixer. I get a high pitched whine with a beeping on top. I was trying to figure out what was going on and noticed that the mouse light was flashing at exactly the same rate as the beeping. Is this a clue? I was hoping this usb thing was going to cure these problems, not introduce more...... This indeed indicates that the noise is caused by USB data transfers that leak through to the analog circuitry. I just read a report about the Audio Kontrol 1 USB audio interface in Sound On Sound. In one paragraph, the author writes: "I regularly monitor from the outputs of a DigiDesign M Box 1, an M-Audio Quattro and a Kore's audio outs, and the AK 1's output sounded easily the best with an obvious increase of clarity and depth. One of the reasons is that it's the only USB interface I've used that completely cleans up the interference that some G5 towers (including mine) have a habit of imparting to audio signals" So apparently most USB audio device are not that well designed. Meindert |
#86
Posted to rec.audio.pro
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USB hum/noise isolation?
"StudioDog" wrote in message
oups.com... On Mar 24, 9:37 pm, "Richard Crowley" wrote: It seems highly unlikely that this has anything to do with software. So your opinion would be that the glitch lies in the A/D/A converters in the interface? That is also my opinion. Meindert |
#87
Posted to rec.audio.pro
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USB hum/noise isolation?
"StudioDog" wrote ...
"Richard Crowley" wrote: It seems highly unlikely that this has anything to do with software. So your opinion would be that the glitch lies in the A/D/A converters in the interface? Yes. Designing A/D or D/A circuits that have zero artifacts from the digital signals is not trivial. What you are hearing could be "normal" for a low-end piece of equipment. If you want to be specific, no, I don't think the problem is necessarily with the integrated circuit itself, but with the overall circuit design and/or the physical layout, etc. |
#88
Posted to rec.audio.pro
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USB hum/noise isolation?
Meindert Sprang wrote:
"StudioDog" wrote in message On Mar 24, 9:37 pm, "Richard Crowley" wrote: It seems highly unlikely that this has anything to do with software. So your opinion would be that the glitch lies in the A/D/A converters in the interface? That is also my opinion. I think I have said this at least twice in this thread. If the problem is not a ground loop, it is a broken unit or a design issue. You might look at Dan Lavry's USB interface. $200 for two analogue inputs. It actually works. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." |
#89
Posted to rec.audio.pro
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USB hum/noise isolation?
StudioDog wrote:
John - your symptoms seem too much like mine to be a separate problem! I haven't played with buffer settings too much, as I figured if the noise was present in both of my usb interfaces (Alesis multimix8 and Behringer UCA202) the trouble was systemic. Up til your post I thought I was the only one experiencing this! Now at least I know I'm not totally crazy! I don't know enough a out the techie side of USB to guess where the problem might lie, but I think it's safe to say that there IS a real issue here! As I can't currently afford to buy a more expensive interface, I'm going to try cutting the noise out of my monitor path with a transformer isolation box between the interface (behringer unit) and the mixer Tape In's (try as I might, I can't find any affordable product that will isolate the USB line itself, so I'm bypassing the Alesis usb port altogether). I've got an ART DTI dual transformer isolation box on order from my local shop - I'll let you know if it does the trick! Like Red Green says, "We're all in this together!" Strangely enough, I hear USB digital flow in the PC speakers but not in the output of the USB device... Philippe |
#90
Posted to rec.audio.pro
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USB hum/noise isolation?
I've got an ART DTI dual transformer isolation box on order from my
local shop - I'll let you know if it does the trick! If you hear noise on the outputs with a headphone plugged right into them, transformer isolation isn't going to do you a bit of good. Strangely enough, I hear USB digital flow in the PC speakers but not in the output of the USB device... WHAT? What PC speakers are you talking about? Are you just changing all the rules completely here? You have a USB interface, with outputs that are noisy when something is plugged into them, but inputs that are clean. Where did these "PC speakers" come from? --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." |
#91
Posted to rec.audio.pro
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USB hum/noise isolation?
Scott Dorsey wrote:
I've got an ART DTI dual transformer isolation box on order from my local shop - I'll let you know if it does the trick! If you hear noise on the outputs with a headphone plugged right into them, transformer isolation isn't going to do you a bit of good. Strangely enough, I hear USB digital flow in the PC speakers but not in the output of the USB device... WHAT? What PC speakers are you talking about? Are you just changing all the rules completely here? You have a USB interface, with outputs that are noisy when something is plugged into them, but inputs that are clean. Where did these "PC speakers" come from? --scott I'm NOT StudioDog... I just made a comment ! As if rederecting speaker output to ASIO out should add noise to the signal... Philippe sleepy |
#92
Posted to rec.audio.pro
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USB hum/noise isolation?
On Mar 25, 10:21 am, (Scott Dorsey) wrote:
Meindert Sprang wrote: "StudioDog" wrote in message On Mar 24, 9:37 pm, "Richard Crowley" wrote: You might look at Dan Lavry's USB interface. $200 for two analogue inputs. It actually works. Hi Scott. What model are you referring to here? I'd like to check it out. Thanks |
#93
Posted to rec.audio.pro
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USB hum/noise isolation?
StudioDog wrote:
On Mar 25, 10:21 am, (Scott Dorsey) wrote: Meindert Sprang wrote: "StudioDog" wrote in message On Mar 24, 9:37 pm, "Richard Crowley" wrote: You might look at Dan Lavry's USB interface. $200 for two analogue inputs. It actually works. Hi Scott. What model are you referring to here? I'd like to check it out. He only makes one USB interface! Go to the website, click on "computer products" or some such thing, and it's there. It works, it has plenty of gain, and it operates pretty seamlessly. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." |
#94
Posted to rec.audio.pro
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USB hum/noise isolation?
He only makes one USB interface! Go to the website, click on "computer products" or some such thing, and it's there. It works, it has plenty of gain, and it operates pretty seamlessly. --scott OK.....a bit touchy tonight are we? |
#95
Posted to rec.audio.pro
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USB hum/noise isolation?
"StudioDog" wrote ...
He only makes one USB interface! Go to the website, click on "computer products" or some such thing, and it's there. It works, it has plenty of gain, and it operates pretty seamlessly. --scott OK.....a bit touchy tonight are we? Most of us are annoyed by people who don't seem to know what Google is or how to use it. I was able to find it earlier today (although the price seemed to be more like $250) |
#96
Posted to rec.audio.pro
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USB hum/noise isolation?
On Mar 25, 8:59 pm, (Scott Dorsey) wrote:
He only makes one USB interface! Go to the website, click on "computer products" or some such thing, and it's there. It works, it has plenty of gain, and it operates pretty seamlessly. --scott ok.... While we all pause to let Scott grab a beer and relax a bit, those of us not intimately aware of every piece of audio gear out there can follow the link to Lavry Engineering's one (and only - don't forget!) USB interface: http://www.lavryengineering.com/prod...ter_audio.html Too lazy to click and read? I offer my synopsis: The Mini Personal Recording Studio 2 is a small USB interface featuring 2 mic inputs optimized for dynamic mics. Seems simple enough. My only difficulty with it is that the unit is essentially only half a system - there is no playback/monitor output provided, so you have to use the computer's soundcard outputs. Not sure how this might affect latency while overdubbing a previously recorded track, etc. |
#97
Posted to rec.audio.pro
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USB hum/noise isolation?
Most of us are annoyed by people who don't seem
to know what Google is or how to use it. I was able to find it earlier today (although the price seemed to be more like $250) Thanks for weighing in on my incompetency, Richard. I truly appreciate your helpful post. Let's see, now....Google.... I heard about that once.... 10 pages into a Google search for "Lavry Mini Personal Recording Studio 2", I found a post that Dan Lavry had made to a Harmony Central forum in Jan of 2004 announcing the launch of the product. He did mention a price of $250 - over 3 years ago! Sorry, but I assumed from Scott's "what the hell planet are you on?" post that the Lavry USB interface was a widely available product that I should have already been aware of. I ignore 3-year-old forum posts in favour of, for instance, online vendor product pages with specs, pricing, user reviews, etc. As I found none of these things, I thought I'd inquire from the original source - Scott, in this case - for clarification. It's a little hard to audition a piece of gear when you can't find anyone selling it! I did check on the Lavry website for dealers (surprised you with my onlince cunning, didn't I). Curiosly enough, all 3 purchase methods touted by the Lavry site are "under construction", even their list of dealers..... |
#98
Posted to rec.audio.pro
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USB hum/noise isolation?
StudioDog wrote:
Too lazy to click and read? I offer my synopsis: The Mini Personal Recording Studio 2 is a small USB interface featuring 2 mic inputs optimized for dynamic mics. Seems simple enough. My only difficulty with it is that the unit is essentially only half a system - there is no playback/monitor output provided, so you have to use the computer's soundcard outputs. Not sure how this might affect latency while overdubbing a previously recorded track, etc. Yup, inputs only. Mike preamps are surprisingly good, and you can pad a line input down into it with no problem. If you need phantom power, use an external phantom supply for an extra hundred bucks or so from Rane or Stewart. It ain't no Prism, but for $200 you're getting a whole lot. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." |
#99
Posted to rec.audio.pro
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USB hum/noise isolation?
StudioDog wrote:
Sorry, but I assumed from Scott's "what the hell planet are you on?" post that the Lavry USB interface was a widely available product that I should have already been aware of. I ignore 3-year-old forum posts in favour of, for instance, online vendor product pages with specs, pricing, user reviews, etc. As I found none of these things, I thought I'd inquire from the original source - Scott, in this case - for clarification. It's a little hard to audition a piece of gear when you can't find anyone selling it! Lavry is pretty much a high end manufacturer and this is pretty much their only foray into the bottom end of the market. As a result, they have a pretty small but dedicated dealer network. Give them a call on the phone and they'll get you one for audition. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." |
#100
Posted to rec.audio.pro
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USB hum/noise isolation?
On Mar 26, 9:53 am, (Scott Dorsey) wrote:
StudioDog wrote: Sorry, but I assumed from Scott's "what the hell planet are you on?" post that the Lavry USB interface was a widely available product that I should have already been aware of. I ignore 3-year-old forum posts in favour of, for instance, online vendor product pages with specs, pricing, user reviews, etc. As I found none of these things, I thought I'd inquire from the original source - Scott, in this case - for clarification. It's a little hard to audition a piece of gear when you can't find anyone selling it! Lavry is pretty much a high end manufacturer and this is pretty much their only foray into the bottom end of the market. As a result, they have a pretty small but dedicated dealer network. Give them a call on the phone and they'll get you one for audition. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." Thanks, Scott. I appreciate the info. Now that I know there are more people out there suffering through the Alesis/Behringer USB interface hell, I'll be taking a good long look at possible upgrades. --StudioDog |
#101
Posted to rec.audio.pro
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USB hum/noise isolation?
Richard Crowley wrote:
"StudioDog" wrote ... "Richard Crowley" wrote: It seems highly unlikely that this has anything to do with software. So your opinion would be that the glitch lies in the A/D/A converters in the interface? Yes. Designing A/D or D/A circuits that have zero artifacts from the digital signals is not trivial. That may be the understaement of the century... Designing A/D or D/A circuits that have zero artifacts from the digital signals is pretty much impossible... -- Aaron |
#102
Posted to rec.audio.pro
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USB hum/noise isolation?
wrote ...
Richard Crowley wrote: "StudioDog" wrote ... "Richard Crowley" wrote: It seems highly unlikely that this has anything to do with software. So your opinion would be that the glitch lies in the A/D/A converters in the interface? Yes. Designing A/D or D/A circuits that have zero artifacts from the digital signals is not trivial. That may be the understaement of the century... Designing A/D or D/A circuits that have zero artifacts from the digital signals is pretty much impossible... I meant specifically digital hash leaking into the analog audio parts of the circuit. But your point is also valid. |
#103
Posted to rec.audio.pro
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USB hum/noise isolation?
wrote in message
Richard Crowley wrote: "StudioDog" wrote ... "Richard Crowley" wrote: It seems highly unlikely that this has anything to do with software. So your opinion would be that the glitch lies in the A/D/A converters in the interface? Yes. Designing A/D or D/A circuits that have zero artifacts from the digital signals is not trivial. That may be the understaement of the century... Designing A/D or D/A circuits that have zero artifacts from the digital signals is pretty much impossible... If you look closely at the performance of the better modern converters, it is likely that their largest artifacts are on their analog sides. |
#104
Posted to rec.audio.pro
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USB hum/noise isolation?
"Richard Crowley" wrote in message
wrote ... Richard Crowley wrote: "StudioDog" wrote ... "Richard Crowley" wrote: It seems highly unlikely that this has anything to do with software. So your opinion would be that the glitch lies in the A/D/A converters in the interface? Yes. Designing A/D or D/A circuits that have zero artifacts from the digital signals is not trivial. That may be the understaement of the century... Designing A/D or D/A circuits that have zero artifacts from the digital signals is pretty much impossible... I meant specifically digital hash leaking into the analog audio parts of the circuit. That comes under the heading of "mixed signal" circuit design, which is still a bit of an art. Since digital circuits running at TTL levels are still very common in audio production equipment, keeping those 5 volt square waves out of the analog circuits can be non trivial. The better designs, especially high quality audio interfaces on PCI cards, amaze me. But, even external converters have this same basic problem to solve. |
#105
Posted to rec.audio.pro
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USB hum/noise isolation?
Arny Krueger wrote:
wrote in message Richard Crowley wrote: "StudioDog" wrote ... "Richard Crowley" wrote: It seems highly unlikely that this has anything to do with software. So your opinion would be that the glitch lies in the A/D/A converters in the interface? Yes. Designing A/D or D/A circuits that have zero artifacts from the digital signals is not trivial. That may be the understaement of the century... Designing A/D or D/A circuits that have zero artifacts from the digital signals is pretty much impossible... If you look closely at the performance of the better modern converters, it is likely that their largest artifacts are on their analog sides. True - and you can certainly make digital artifacts be so far down as to be inaudible. Good luck having "zero artifacts" though... -- Aaron |
#106
Posted to rec.audio.pro
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USB hum/noise isolation?
wrote in message
Arny Krueger wrote: wrote in message Richard Crowley wrote: "StudioDog" wrote ... "Richard Crowley" wrote: It seems highly unlikely that this has anything to do with software. So your opinion would be that the glitch lies in the A/D/A converters in the interface? Yes. Designing A/D or D/A circuits that have zero artifacts from the digital signals is not trivial. That may be the understaement of the century... Designing A/D or D/A circuits that have zero artifacts from the digital signals is pretty much impossible... If you look closely at the performance of the better modern converters, it is likely that their largest artifacts are on their analog sides. True - and you can certainly make digital artifacts be so far down as to be inaudible. Good luck having "zero artifacts" though... Agreed that nothing is perfect. However, perfection to the point where there is no practical impact does seem possible, and in some cases even likely. |
#107
Posted to rec.audio.pro
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USB hum/noise isolation?
Arny Krueger wrote:
wrote in message Arny Krueger wrote: wrote in message Richard Crowley wrote: "StudioDog" wrote ... "Richard Crowley" wrote: It seems highly unlikely that this has anything to do with software. So your opinion would be that the glitch lies in the A/D/A converters in the interface? Yes. Designing A/D or D/A circuits that have zero artifacts from the digital signals is not trivial. That may be the understaement of the century... Designing A/D or D/A circuits that have zero artifacts from the digital signals is pretty much impossible... If you look closely at the performance of the better modern converters, it is likely that their largest artifacts are on their analog sides. True - and you can certainly make digital artifacts be so far down as to be inaudible. Good luck having "zero artifacts" though... Agreed that nothing is perfect. However, perfection to the point where there is no practical impact does seem possible, and in some cases even likely. In the audio world, definitely. It doesn't even have to that close to perfection in that case - don't take that to mean I'm claiming it is easy though... -- Aaron |
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