Beta-test: DeltaWave Null Comparison software

[pkane]

BTW, which is white and which is blue for the Matched spectra charr? Thx!

Look at the color on the play button next to reference and comparison file names. The color on those buttons corresponds to the colors on the chart.

 

[Pdxwayne]

Look at the color on the play button next to reference and comparison file names. The color on those buttons corresponds to the colors on the chart.

Thanks! So my ADC totally no good? Or good up to certain freq, like up to 14khz? Or give up on it and buy something decent?

 

[pkane]

Thanks! So my ADC totally no good? Or good up to certain freq, like up to 14khz? Or give up on it and buy something decent?

Good up to about 14kHz. But it isn’t a low distortion device, so trying to measure and compare higher quality DACs with it isn’t going to give you good results, even below 14k

 

[Pdxwayne]

Good up to about 14kHz. But it isn’t a low distortion device, so trying to measure and compare higher quality DACs with it isn’t going to give you good results, even below 14k

Thanks for all the help!

 

[Pdxwayne]

The max input on a UCA202 is 1.25 volts. Which is low, and you might be at times exceeding that. It also has rather poor SNR of 89 dbA at 1 khz. And distortion at -10 db is -66 db, but could be worse at high input levels. So I'd say all these reasons are why your results are poor.

Oh, it is also a 16 bit ADC. So that is another part of the issue if you are feeding it 24 bit signals.

Yeah, it seems all the time I spent capturing files and comparing DAC pretty much wasted.
: (

Anyway, I was comparing CD quality files.

Any suggestions for low cost, but accurate ADC?

Thanks!

 

[Blumlein 88]

Yeah, it seems all the time I spent capturing files and comparing DAC pretty much wasted.
: (

Anyway, I was comparing CD quality files.

Any suggestions for low cost, but accurate ADC?

Thanks!

Focusrite Scarlett 2i2 3rd gen. $170
https://www.audiosciencereview.com/...rlett-2i2-audio-interface-gen-3-review.10187/

I would probably look for a 2nd hand 2i4 which should work as well since it has a few more connections. The 2i2 is spartan as far as connections go.

Motu M2 $180 or so.
https://www.audiosciencereview.com/forum/index.php?threads/motu-m2-review-audio-interface.19911/

Of course these are a fair bit more than you likely paid for your UAC 202. And they still are short of measuring the limits of most DACs. DACs, especially for the price, are a little bit more developed than ADC's at this point. To step up ADC above the performance of those listed above you'll likely need to spend something like $600 and even those won't equal the top performance of DACs.

 

[Pdxwayne]

Focusrite Scarlett 2i2 3rd gen. $170
https://www.audiosciencereview.com/...rlett-2i2-audio-interface-gen-3-review.10187/

I would probably look for a 2nd hand 2i4 which should work as well since it has a few more connections. The 2i2 is spartan as far as connections go.

Motu M2 $180 or so.
https://www.audiosciencereview.com/forum/index.php?threads/motu-m2-review-audio-interface.19911/

Of course these are a fair bit more than you likely paid for your UAC 202. And they still are short of measuring the limits of most DACs. DACs, especially for the price, are a little bit more developed than ADC's at this point. To step up ADC above the performance of those listed above you'll likely need to spend something like $600 and even those won't equal the top performance of DACs.

I do have 3rd gen Scarlett Solo. I will try using the xlr input (using RCA to XLR cable from DAC) for single channel capture. Sounds reasonable?

Should be better than UCA202, correct?

Thanks!

 

[Blumlein 88]

I do have 3rd gen Scarlett Solo. I will try using the xlr input (using RCA to XLR cable from DAC) for single channel capture. Sounds reasonable?

Should be better than UCA202, correct?

Thanks!

Yes it should be obviously better. If you only want one channel for measuring that's a good choice.

 

[Pdxwayne]

The scarlett solo is better than the uca202. However, scarlett solo seems still have high freq issue? So, it is good until how many Khz? Note that this is just a comparison of CD quality file. Thanks!

Orig vs DAC1:

Orig vs DAC2:

 

[Pdxwayne]

Using Scarlett Solo, comparison between DAC is below. Anything obvious that is audible? Thanks!

 

[pkane]

Using Scarlett Solo, comparison between DAC is below. Anything obvious that is audible? Thanks!

View attachment 113471

Strange that we see a similar increase in frequency error, except it's shifted a bit higher in frequency, by another 1kHz or so.

I can't imagine it's audible, considering most music at those frequencies is at a very low level already, and our ears are not very sensitive there.

Still, looks a bit strange, and maybe worth investigating some settings on the loopback devices (filter setting, for example). Here's more of what I'm used to seeing:

 

[pkane]

Using Scarlett Solo, comparison between DAC is below. Anything obvious that is audible? Thanks!

View attachment 113471

The thing that bothers me is that the difference looks like noise rather than a filter cutoff. It's almost like there's increasing noise with frequency coming from somewhere. But I think we've determined it's not coming from the ADC, and it's happening with both DACs, so... what's left? Software that captures the recording or the player?

 

[Pdxwayne]

Strange that we see a similar increase in frequency error, except it's shifted a bit higher in frequency, by another 1kHz or so.

I can't imagine it's audible, considering most music at those frequencies is at a very low level already, and our ears are not very sensitive there.

Still, looks a bit strange, and maybe worth investigating some settings on the loopback devices (filter setting, for example). Here's more of what I'm used to seeing:
View attachment 113475

Hmm, my test file is played from Node2i (from USB disk), send to DAC via Coaxial, then DAC RCA to Scarlett Solo, then Scarlett Solo USB to Laptop and captured using Audacity. I wonder where is the weak link....

 

[pkane]

Hmm, my test file is played from Node2i (from USB disk), send to DAC via Coaxial, then DAC RCA to Scarlett Solo, then Scarlett Solo USB to Laptop and captured using Audacity. I wonder where is the weak link....

Can you try playing and capturing at a higher sampling rate? Say 96kHz?

 

[Pdxwayne]

Can you try playing and capturing at a higher sampling rate? Say 96kHz?

My files are all CD quality. Not sure how to get my chain to play at 96kHz. Also, Audacity export to WAV option don't seems to have 96KHz option....

Still, this is a very good learning experience. Thanks!

 

[pkane]

My files are all CD quality. Not sure how to get my chain to play at 96kHz. Also, Audacity export to WAV option don't seems to have 96KHz option....

Still, this is a very good learning experience. Thanks!

In Audacity you'll need to set the sampling rate for your project, and then do tracks->resample to the desired frequency. Can't help with Node2i

 

[Pdxwayne]

In Audacity you'll need to set the sampling rate for your project, and then do tracks->resample to the desired frequency. Can't help with Node2i

Hmm, it is Audacity problem. Strange.

If I open a WAV file in Audacity and export that file as WAV, then that original WAV and exported file comparison would show that difference. If I use Windows to do file copy, the Windows duplicated file shows no difference.

So "export to WAV" function in Audacity is no good! : (

May I know what would be another alternative to Audacity that won't mess up export file? Thanks!

Here is WAV file comparison with its own exported file:

 

[Blumlein 88]

Hmm, it is Audacity problem. Strange.

If I open a WAV file in Audacity and export that file as WAV, then that original WAV and exported file comparison would show that difference. If I use Windows to do file copy, the Windows duplicated file shows no difference.

So "export to WAV" function in Audacity is no good! : (

May I know what would be another alternative to Audacity that won't mess up export file? Thanks!

Here is WAV file comparison with its own exported file:
View attachment 113478

Sounds like you have dither selected in preferences in Audacity. If you aren't changing bit depth or sample rate you don't want to dither when you save the file.

Under Audacity Preferences, look under Quality and for Real time and High Quality conversion select NONE in the drop down menu. Now when you save the file it won't be dithered and will be bit identical when you open it back up.

 

[Pdxwayne]

Sounds like you have dither selected in preferences in Audacity. If you aren't changing bit depth or sample rate you don't want to dither when you save the file.

Under Audacity Preferences, look under Quality and for Real time and High Quality conversion select NONE in the drop down menu. Now when you save the file it won't be dithered and will be bit identical when you open it back up.

Thanks!

I will try it out and do more comparisons. : )

 

[Pdxwayne]

Sounds like you have dither selected in preferences in Audacity. If you aren't changing bit depth or sample rate you don't want to dither when you save the file.

Under Audacity Preferences, look under Quality and for Real time and High Quality conversion select NONE in the drop down menu. Now when you save the file it won't be dithered and will be bit identical when you open it back up.

I followed your tips and also make sure I export at consistent 32-bit floating rate (previously I was comparing exported files at 16-bit floating rate with original file at 32-bit floating).

With that, the DAC vs Original file comparison looks a lot better. Below are DAC1 vs Orig, DAC2 vs Orig, and DAC1 vs DAC2. Regarding DAC vs DAC comparison, any audible differences? Note that this is just one channel. Two channels the difference might be larger? Thanks!

DAC1 vs Orig

DAC2 vs Orig:

DAC vs DAC: