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StudioDog StudioDog is offline
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Default 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!"

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StudioDog StudioDog is offline
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Default 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   Report Post  
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Richard Crowley Richard Crowley is offline
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Default 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.


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StudioDog StudioDog is offline
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Default 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?

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Meindert Sprang Meindert Sprang is offline
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Default 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




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Meindert Sprang Meindert Sprang is offline
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Default 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



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Richard Crowley Richard Crowley is offline
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Default 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   Report Post  
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Scott Dorsey Scott Dorsey is offline
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Default 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."
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Philippe Lemaire \(remove oldies\) Philippe Lemaire \(remove oldies\) is offline
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Default 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


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Scott Dorsey Scott Dorsey is offline
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Default 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   Report Post  
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Philippe Lemaire \(remove oldies\) Philippe Lemaire \(remove oldies\) is offline
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Default 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



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StudioDog StudioDog is offline
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Default 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

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Scott Dorsey Scott Dorsey is offline
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Default 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."
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StudioDog StudioDog is offline
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Default 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?


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Richard Crowley Richard Crowley is offline
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Default 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)



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StudioDog StudioDog is offline
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Default 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   Report Post  
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StudioDog StudioDog is offline
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Default 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   Report Post  
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Scott Dorsey Scott Dorsey is offline
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Default 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."
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Scott Dorsey Scott Dorsey is offline
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Default 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."
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StudioDog StudioDog is offline
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Default 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



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No Name
 
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Default 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   Report Post  
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Richard Crowley Richard Crowley is offline
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Default 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.


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Arny Krueger Arny Krueger is offline
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Default 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   Report Post  
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Arny Krueger Arny Krueger is offline
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Default 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.


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No Name
 
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Default 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


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Arny Krueger Arny Krueger is offline
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Default 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.


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No Name
 
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Default 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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