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[email protected] mainmachine_pleasenospam_@choiceonemail.com is offline
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Default A/D converter- replace crystal unit?

OK, I'd like to get some input on this one, as there may be some
"unknown unknowns" to consider:

(opens can of worms)

I have several M Audio Delta 1010LT souncards that I have been using
successfully for multitracking in a DAW of my own assemblage.
Recently, a friend of mine mentioned that Black Lion Audio is offering
an upgrade package for the 1010. I was intrigued, and did some
comparative listening to recordings I've made through the 1010's and
recordings I made a few years back on a Roland VSR-880. I noticed a
difference in the sound quality- I perceived less clarity in the newer
recordings. I will mention that everything has been tracked through
the same mics and preamps, the only difference is the Roland vs. the
PC with the Delta setup. It seems to make sense to me that there may
be some benefits to upgrading the 1010's, and in fact the PC itself.

I have replaced capacitors in ATX PSU's and motherboards before, (for
different reasons) and noticed improved stability and increased
performance. (In this case, I was replacing poorly designed capacitors
with better-quality parts). Due to the low cost of DIY, I figured I
could do better than G Luxon caps on the PSU rails of the 1010's, and
bumped them up from 470uF to Nichicon 1000uF low-ESR types, complete
with film bypass caps.

OK, that should feed the flames enough, right?

But there's more- BLA will also upgrade the "clock" on your 1010. I've
stared at a few datasheets, and it seems that there are tighter
tolerance parts available than that of the stock card. So here's my
question for those who have experience with A/D clock design: Is there
more to it than just swapping out the crystal with a better spec'd
part?

Due to the low cost of both the soundcards and the crystals, it would
be pretty easy to set up a comparative test. If you have more than one
card, you normally sync them up via SPDIF and choose one as the
"master clock". You could install the new crystal in one card, then
run a parallel A/D and/or D/A test, specifying a different card as the
master clock for each run. Sound good?

Great! But how do I analyze the results? Arny, I know you're familiar
with these cards- any recommendations on how I can test for jitter?
(sorry to single you out, but I've read your posts on the 1010LT, and
I figured you'd sympathize with a fellow user).

Thanks in advance for your replies- this should be interesting! (and
hopefully useful!)

-dave M.

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Mike Rivers Mike Rivers is offline
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Default A/D converter- replace crystal unit?

On Mar 25, 8:21 pm, "
wrote:

question for those who have experience with A/D clock design: Is there
more to it than just swapping out the crystal with a better spec'd
part?


The crystal is just part of the clock. The actual clock signal, if
this is typical of an A/D converter, comes from a phase locked loop
circuit which uses the crystal as a reference, but because of a long
time constant, has greater short term stability than the crystal
itself. Better clocks have better PLLs. So he may be using better
grade capacitor, he may change the loop gain, he may even change the
circuit. The thing about people who upgrade commercial product (like
Black Lion and Audio Upgrades) is that they study out the whole
circuit and most of the time do more than the obvious. And often the
obvious (like use a "better" op amp) requires changing or adding some
other circuit components.

The thing is that they have the schematic and you and I (or at least
I) don't. What you're paying for is what they've learned.






Due to the low cost of both the soundcards and the crystals, it would
be pretty easy to set up a comparative test. If you have more than one
card, you normally sync them up via SPDIF and choose one as the
"master clock". You could install the new crystal in one card, then
run a parallel A/D and/or D/A test, specifying a different card as the
master clock for each run. Sound good?

Great! But how do I analyze the results? Arny, I know you're familiar
with these cards- any recommendations on how I can test for jitter?
(sorry to single you out, but I've read your posts on the 1010LT, and
I figured you'd sympathize with a fellow user).

Thanks in advance for your replies- this should be interesting! (and
hopefully useful!)

-dave M.



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Scott Dorsey Scott Dorsey is offline
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Default A/D converter- replace crystal unit?

Due to the low cost of both the soundcards and the crystals, it would
be pretty easy to set up a comparative test. If you have more than one
card, you normally sync them up via SPDIF and choose one as the
"master clock". You could install the new crystal in one card, then
run a parallel A/D and/or D/A test, specifying a different card as the
master clock for each run. Sound good?


Odds are he's doing more than just changing the crystal to clean up the
clock.

I do question, though, the wisdom of spending money on a cheap soundcard
to improve the sound quality, when there are known-good A/D boxes available
off the shelf for a little more money. You upgrade this, then upgrade
that, and next thing you know you could have bought the Benchmark with
what you spent.

Great! But how do I analyze the results? Arny, I know you're familiar
with these cards- any recommendations on how I can test for jitter?
(sorry to single you out, but I've read your posts on the 1010LT, and
I figured you'd sympathize with a fellow user).


Problem is that you need a signal source that is really good. For example,
if you record a 1 KC sine wave, clock jitter will show up as little sidebands
around the main peak if you do an FFT. But, if you record a 1KC sine wave
from a 200CD oscillator like the one on my bench, you'll see lots of little
sidebands that came from the oscillator itself and aren't artifacts of the
conversion. In order to measure the converter quality, you need accurate
signal sources and analysis tools that are an order of magnitude tighter
than what you're trying to measure. That's why this is so hard.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."
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Default A/D converter- replace crystal unit?

On Mar 25, 8:03 pm, (Scott Dorsey) wrote:
Due to the low cost of both the soundcards and the crystals, it would
be pretty easy to set up a comparative test. If you have more than one
card, you normally sync them up via SPDIF and choose one as the
"master clock". You could install the new crystal in one card, then
run a parallel A/D and/or D/A test, specifying a different card as the
master clock for each run. Sound good?


Odds are he's doing more than just changing the crystal to clean up the
clock.

I do question, though, the wisdom of spending money on a cheap soundcard
to improve the sound quality, when there are known-good A/D boxes available
off the shelf for a little more money. You upgrade this, then upgrade
that, and next thing you know you could have bought the Benchmark with
what you spent.


Well, I guess it's not a matter of wisdom, per se, but more a matter
of trying to extend the usefulness of a given device, while learning
about the general class of device in the process. I feel it helps me
to understand what to look for when I'm "kicking the tires" on the
next potential new vehicle.

Great! But how do I analyze the results? Arny, I know you're familiar
with these cards- any recommendations on how I can test for jitter?
(sorry to single you out, but I've read your posts on the 1010LT, and
I figured you'd sympathize with a fellow user).


Problem is that you need a signal source that is really good. For example,
if you record a 1 KC sine wave, clock jitter will show up as little sidebands
around the main peak if you do an FFT. But, if you record a 1KC sine wave
from a 200CD oscillator like the one on my bench, you'll see lots of little
sidebands that came from the oscillator itself and aren't artifacts of the
conversion. In order to measure the converter quality, you need accurate
signal sources and analysis tools that are an order of magnitude tighter
than what you're trying to measure. That's why this is so hard.
--scott


That's what I was afraid of... but for less than a dollar and five
minutes of my time, I might just go ahead and do it. The worst cast
would be that there's no improvement, or I have to replace the card
(at which point I will hopefully remember your previous reference to
wisdom!

Thanks for the $.02!

-dave M.

--
"C'est un Nagra. C'est suisse, et tres, tres precis."


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Arny Krueger Arny Krueger is offline
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Posts: 17,262
Default A/D converter- replace crystal unit?

"
wrote in message
oups.com
OK, I'd like to get some input on this one, as there may
be some "unknown unknowns" to consider:

(opens can of worms)

I have several M Audio Delta 1010LT souncards that I have
been using successfully for multitracking in a DAW of my
own assemblage. Recently, a friend of mine mentioned that
Black Lion Audio is offering an upgrade package for the
1010. I was intrigued, and did some comparative listening
to recordings I've made through the 1010's and recordings
I made a few years back on a Roland VSR-880. I noticed a
difference in the sound quality- I perceived less clarity
in the newer recordings.



There's your first logical mistake - the use of a less-than-reference
quality standard, the Roland VSR-880. I'm not saying that *your* Roland
VSR-880 is less than sonically transparent, but there's no a priori reason
to believe that it remains perfectly transparent.

I'm not saying that *your* 1010LT is sonically transparent, but there's no a
priori reason to believe that it is less than sonically transparent. What
I'm saying is that you are comparing 2 unknowns. If they are the same or
different, what does that mean?

On top of that, there's some doubt that your comparison was
carefully-controlled, IOW recordings of the identical same inputs,
level-matched and blind.

I'm not saying that *your* 1010LT is sonically transparent, but there's no a
priori reason to believe that it is less than sonically transparent. What
I'm saying is that you are comparing 2 unknowns. If they are the same or
different, what does that mean?

The *right* way to test an audio interface is to loop the outputs to the
inputs, re-record some representative music, and then do a blind, level
matched comparison of the origional recording to the copy. Then, you're
comparing your audio interface to a known standard - whatever you used to
tie the inputs to the outputs, which in the case of the 1010LT is its
built-in connector bundle.

If you have even the most basic DAW software and skills, you can set this up
as a comparison of 2 level-matched, time-synched stereo .wav files using
test administration software that you can download for free from
www.pcabx.com .

You can apply this technique to both the 1010LT and the Roland VSR-880. You
might be surprised by the results.




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Default A/D converter- replace crystal unit?

On Mar 26, 9:23 am, "Arny Krueger" wrote:
"main wrote in message

oups.com

OK, I'd like to get some input on this one, as there may
be some "unknown unknowns" to consider:


(opens can of worms)


I have several M Audio Delta 1010LT souncards that I have
been using successfully for multitracking in a DAW of my
own assemblage. Recently, a friend of mine mentioned that
Black Lion Audio is offering an upgrade package for the
1010. I was intrigued, and did some comparative listening
to recordings I've made through the 1010's and recordings
I made a few years back on a Roland VSR-880. I noticed a
difference in the sound quality- I perceived less clarity
in the newer recordings.


There's your first logical mistake - the use of a less-than-reference
quality standard, the Roland VSR-880. I'm not saying that *your* Roland
VSR-880 is less than sonically transparent, but there's no a priori reason
to believe that it remains perfectly transparent.

I'm not saying that *your* 1010LT is sonically transparent, but there's no a
priori reason to believe that it is less than sonically transparent. What
I'm saying is that you are comparing 2 unknowns. If they are the same or
different, what does that mean?

On top of that, there's some doubt that your comparison was
carefully-controlled, IOW recordings of the identical same inputs,
level-matched and blind.

I'm not saying that *your* 1010LT is sonically transparent, but there's no a
priori reason to believe that it is less than sonically transparent. What
I'm saying is that you are comparing 2 unknowns. If they are the same or
different, what does that mean?

The *right* way to test an audio interface is to loop the outputs to the
inputs, re-record some representative music, and then do a blind, level
matched comparison of the origional recording to the copy. Then, you're
comparing your audio interface to a known standard - whatever you used to
tie the inputs to the outputs, which in the case of the 1010LT is its
built-in connector bundle.

If you have even the most basic DAW software and skills, you can set this up
as a comparison of 2 level-matched, time-synched stereo .wav files using
test administration software that you can download for free fromwww.pcabx.com.

You can apply this technique to both the 1010LT and the Roland VSR-880. You
might be surprised by the results.


This is completely correct and reasonable. I may very well have heard
a difference because I wanted to. Does Rightmark provide any useful
tools for this kind of test? Man, what I wouldn't do for some really
high-grade testing equipment!

-dave M.

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Arny Krueger Arny Krueger is offline
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Posts: 17,262
Default A/D converter- replace crystal unit?

"
wrote in message
oups.com
On Mar 26, 9:23 am, "Arny Krueger"
wrote:
"main
wrote in message

oups.com

OK, I'd like to get some input on this one, as there may
be some "unknown unknowns" to consider:


(opens can of worms)


I have several M Audio Delta 1010LT souncards that I
have been using successfully for multitracking in a DAW
of my own assemblage. Recently, a friend of mine
mentioned that Black Lion Audio is offering an upgrade
package for the 1010. I was intrigued, and did some
comparative listening to recordings I've made through
the 1010's and recordings I made a few years back on a
Roland VSR-880. I noticed a difference in the sound
quality- I perceived less clarity in the newer
recordings.


There's your first logical mistake - the use of a
less-than-reference
quality standard, the Roland VSR-880. I'm not saying
that *your* Roland
VSR-880 is less than sonically transparent, but there's
no a priori reason
to believe that it remains perfectly transparent.

I'm not saying that *your* 1010LT is sonically
transparent, but there's no a
priori reason to believe that it is less than sonically
transparent. What
I'm saying is that you are comparing 2 unknowns. If they
are the same or
different, what does that mean?

On top of that, there's some doubt that your comparison
was
carefully-controlled, IOW recordings of the identical
same inputs,
level-matched and blind.

I'm not saying that *your* 1010LT is sonically
transparent, but there's no a
priori reason to believe that it is less than sonically
transparent. What
I'm saying is that you are comparing 2 unknowns. If they
are the same or
different, what does that mean?

The *right* way to test an audio interface is to loop
the outputs to the
inputs, re-record some representative music, and then do
a blind, level
matched comparison of the origional recording to the
copy. Then, you're
comparing your audio interface to a known standard -
whatever you used to
tie the inputs to the outputs, which in the case of the
1010LT is its
built-in connector bundle.

If you have even the most basic DAW software and skills,
you can set this up
as a comparison of 2 level-matched, time-synched stereo
.wav files using
test administration software that you can download for
free fromwww.pcabx.com.

You can apply this technique to both the 1010LT and the
Roland VSR-880. You
might be surprised by the results.


This is completely correct and reasonable. I may very
well have heard a difference because I wanted to.


Or, due to level mismatch, or actual defective equipment. Hard to say for
sure.

Does
Rightmark provide any useful tools for this kind of test?


Yes. You can Rightmark the 1010LT and compare your results to these:

http://www.pcavtech.com/soundcards/d...10lt/index.htm

Testing the Roland VSR 880 might take a little careful mouth-holding, but in
prinicple you can Rightmark anything that records and plays. For example,
I've rightmarked CD players by burning my own test CD.


Man, what I wouldn't do for some really high-grade
testing equipment!


You probably already have a good approximation of it in the 1010LT.

The performance shown here is not too far from the origional Audio Precision
test set:

http://www.pcavtech.com/soundcards/d...010lt/2496.htm

But, no way can it be confused with a System 2. You can come close to a
System 2 with a LynxTwo.

The 1010LT might be equal or better than anything that HP or Sound
Technology ever sold.


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[email protected] mainmachine_pleasenospam_@choiceonemail.com is offline
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Posts: 28
Default A/D converter- replace crystal unit?

On Mar 26, 10:11 am, "Arny Krueger" wrote:
"main wrote in message

oups.com





On Mar 26, 9:23 am, "Arny Krueger"
wrote:
"main
wrote in message


groups.com


OK, I'd like to get some input on this one, as there may
be some "unknown unknowns" to consider:


(opens can of worms)


I have several M Audio Delta 1010LT souncards that I
have been using successfully for multitracking in a DAW
of my own assemblage. Recently, a friend of mine
mentioned that Black Lion Audio is offering an upgrade
package for the 1010. I was intrigued, and did some
comparative listening to recordings I've made through
the 1010's and recordings I made a few years back on a
Roland VSR-880. I noticed a difference in the sound
quality- I perceived less clarity in the newer
recordings.


There's your first logical mistake - the use of a
less-than-reference
quality standard, the Roland VSR-880. I'm not saying
that *your* Roland
VSR-880 is less than sonically transparent, but there's
no a priori reason
to believe that it remains perfectly transparent.


I'm not saying that *your* 1010LT is sonically
transparent, but there's no a
priori reason to believe that it is less than sonically
transparent. What
I'm saying is that you are comparing 2 unknowns. If they
are the same or
different, what does that mean?


On top of that, there's some doubt that your comparison
was
carefully-controlled, IOW recordings of the identical
same inputs,
level-matched and blind.


I'm not saying that *your* 1010LT is sonically
transparent, but there's no a
priori reason to believe that it is less than sonically
transparent. What
I'm saying is that you are comparing 2 unknowns. If they
are the same or
different, what does that mean?


The *right* way to test an audio interface is to loop
the outputs to the
inputs, re-record some representative music, and then do
a blind, level
matched comparison of the origional recording to the
copy. Then, you're
comparing your audio interface to a known standard -
whatever you used to
tie the inputs to the outputs, which in the case of the
1010LT is its
built-in connector bundle.


If you have even the most basic DAW software and skills,
you can set this up
as a comparison of 2 level-matched, time-synched stereo
.wav files using
test administration software that you can download for
free fromwww.pcabx.com.


You can apply this technique to both the 1010LT and the
Roland VSR-880. You
might be surprised by the results.

This is completely correct and reasonable. I may very
well have heard a difference because I wanted to.


Or, due to level mismatch, or actual defective equipment. Hard to say for
sure.

Does
Rightmark provide any useful tools for this kind of test?


Yes. You can Rightmark the 1010LT and compare your results to these:

http://www.pcavtech.com/soundcards/d...10lt/index.htm

Testing the Roland VSR 880 might take a little careful mouth-holding, but in
prinicple you can Rightmark anything that records and plays. For example,
I've rightmarked CD players by burning my own test CD.

Man, what I wouldn't do for some really high-grade
testing equipment!


You probably already have a good approximation of it in the 1010LT.

The performance shown here is not too far from the origional Audio Precision
test set:

http://www.pcavtech.com/soundcards/d...010lt/2496.htm

But, no way can it be confused with a System 2. You can come close to a
System 2 with a LynxTwo.

The 1010LT might be equal or better than anything that HP or Sound
Technology ever sold.- Hide quoted text -

- Show quoted text -


Nice! Very helpful- I downloaded Rightmark about a week ago, haven't
gotten to use it yet but now I can't wait to test my system. I'll grab
a copy of that ABX software, too. Thanks, Arny!

What about the issue of jitter when using multiple Delta cards? Could
I try testing one card internally clocked vs. clocked from another
delta? Would jitter show up as the difference between noise figure of
each test? Or will it even be measurable?

-dave M.

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Arny Krueger Arny Krueger is offline
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Posts: 17,262
Default A/D converter- replace crystal unit?

"
wrote in message
oups.com

What about the issue of jitter when using multiple Delta
cards?


There is always jitter, the question is whether or not it is audible.

Could I try testing one card internally clocked
vs. clocked from another delta?


I don't see why not?

Would jitter show up as
the difference between noise figure of each test?


In the spectrum analyzer plots made by the Rightmark program, jitter shows
up as sidebands near large sine waves. For example compare this plot showing
relatively high jitter:

http://www.pcavtech.com/soundcards/d...0_2496/thd.gif

to this similar plot showing relatively low jitter:

http://www.pcavtech.com/soundcards/d...T-2496/thd.png

The relatively high jitter in the delta 1010 plot had a known cause - a weak
cap in the power supply that was not properly filtering the DC power to the
audio circuits. This did not cause audible hum as such, but it did cause FM
modulation of the clock which led to the jitter.

Or will it even be measurable?



http://www.pcavtech.com/soundcards/d...010lt/2496.htm shows miniscule
but barely measuarable amounts of jitter. It could probably be made more
apparent with a more specialized test. However, its more than 120 dB down.
Jitter is inaudible when it is 100+ dB down, so the 1010LT tested was doing
very well indeed.


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Posts: 28
Default A/D converter- replace crystal unit?

On Mar 26, 12:53 pm, "Arny Krueger" wrote:
"main wrote in message

oups.com

What about the issue of jitter when using multiple Delta
cards?


There is always jitter, the question is whether or not it is audible.

Could I try testing one card internally clocked
vs. clocked from another delta?


I don't see why not?

Would jitter show up as
the difference between noise figure of each test?


In the spectrum analyzer plots made by the Rightmark program, jitter shows
up as sidebands near large sine waves. For example compare this plot showing
relatively high jitter:

http://www.pcavtech.com/soundcards/d...0_2496/thd.gif

to this similar plot showing relatively low jitter:

http://www.pcavtech.com/soundcards/d...T-2496/thd.png

The relatively high jitter in the delta 1010 plot had a known cause - a weak
cap in the power supply that was not properly filtering the DC power to the
audio circuits. This did not cause audible hum as such, but it did cause FM
modulation of the clock which led to the jitter.

Or will it even be measurable?


http://www.pcavtech.com/soundcards/d...010lt/2496.htm shows miniscule
but barely measuarable amounts of jitter. It could probably be made more
apparent with a more specialized test. However, its more than 120 dB down.
Jitter is inaudible when it is 100+ dB down, so the 1010LT tested was doing
very well indeed.


OK, I've run some tests using Rightmark on both the 1010LT and the AP
2496 (which I have been using as my 2 buss back into the box) and the
results are interesting. Unless my cards differ greatly from the
average M Audio card, then it seems the AP 2496 has a noisier clock
circuit, or else the card itself is just more sensitive to clock
noise. I also found that I may have some 60 cycle hum to track down,
probably in my patch bay/ effects rack. I don't have anywhere to post
the results, but I can email the html report if anyone is interested
in viewing the results. Remove the obvious from my address to get in
touch with me.

I don't think I need to be concerned with jitter at this point. I only
wish I had thought to use rightmark before *and* after the PSU
upgrade, so I could draw some more definitive conclusions. Jitter and
noise are well below -100 dB almost across the board, even when using
the AP 2496 clock- even better with the 1010LT clock calling the
shots. I plan to do some ABX listening tests as well, to confirm the
RMAA results.

Based on this testing, I think I can live with the Delta 1010LT clock
for now, but I might be able to do better than the AP 2496 for my
stereo bus return. Anyone have any cards they like for this purpose?
RME, Lynx, maybe a different M Audio card?

Arny- how would I go about testing microphones and monitors with RMAA,
considering the fact that there is no perfect microphone/ speaker to
use as the controlled variable? I can borrow an earthworks omni from a
friend of mine, which has a good rep. as a measurement mic, but is
there more to consider?

BTW- Thanks for making such a useful program! I will be testing
everything I own, just to see how things measure.

-dave M.



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Arny Krueger Arny Krueger is offline
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Posts: 17,262
Default A/D converter- replace crystal unit?

"
wrote in message
ps.com

Arny- how would I go about testing microphones and
monitors with RMAA, considering the fact that there is no
perfect microphone/ speaker to use as the controlled
variable? I can borrow an earthworks omni from a friend
of mine, which has a good rep. as a measurement mic, but
is there more to consider?


There's an acoustic measurement option in the options, on the acoustics test
tab.

BTW- Thanks for making such a useful program!


It isn't anything I wrote - I think a Russian wrote it.

I will be testing everything I own, just to see how things measure.


Enjoy!


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