Both DAC are transparent as measures by Amir, why one not as clean sounding as the other?

[Grooved]

I did captures again and carefully trim the beginning and end. Still, although pkmetric is at -105db, the correlated null is still at 64.99dBA.
: (

I don't know which part of the chain is the problem. Maybe my laptop, the apps, the ADC, DAC, etc....

Thanks for all the help. I think I will try a different laptop next.....

Do you know how to run some basic measurements using REW? This can help pinpoint where the problem might be, a few sweeps using frequency, level, THD, etc.

Hi @pkane and @Pdxwayne

I just test the difference on two files I've created in the past with a setup but one with laptop powered by battery, and one with power supply.
I got more than -110 PKmetric in both with/without autotrim (only the correlated null was a bit different) while it was a small different condition (power only), so I think with the same condition, it can only be better than -110

So is it possible that, as he's not using one interface to do the loopback (In and Out on the same device) but a DAC and ADC, he's not getting a perfect sync between both devices ?
Ideally, when you do a loopback, your DAC and your ADC should be synced with a SPDIF or ADAT signal, but I'm not sure if it can change the results by a huge margin ?
In case it can improve the results, he also can't do that because both DAC don't have a digital output to do such a sync

 

[Chrispy]

Oh yeah, one of its best handy features.

Making me wonder why even more why I hadn't seen mention before....must be slippin'

 

[pkane]

Hi @pkane and @Pdxwayne

I just test the difference on two files I've created in the past with a setup but one with laptop powered by battery, and one with power supply.
I got more than -110 PKmetric in both with/without autotrim (only the correlated null was a bit different) while it was a small different condition (power only), so I think with the same condition, it can only be better than -110
View attachment 139963

So is it possible that, as he's not using one interface to do the loopback (In and Out on the same device) but a DAC and ADC, he's not getting a perfect sync between both devices ?
Ideally, when you do a loopback, your DAC and your ADC should be synced with a SPDIF or ADAT signal, but I'm not sure if it can change the results by a huge margin ?
In case it can improve the results, he also can't do that because both DAC don't have a digital output to do such a sync

There is no sync issues between a DAC and an ADC when the same two devices are used to record the same audio clip twice in a row. @Pdxwayne 's results are looking bad when comparing such two loopback recordings over the same DAC and ADC. This should produce a much, much better null than what he's reporting.

 

[pkane]

Same kind of results for X16 right XLR out. I adjusted the dB to match the d30pro RCA dB. I wonder where is the problem in the chain....

View attachment 139938

I suspect the ADC, since both DACs should show much better performance than this. Didn't we go through these tests with you a while back where the ADC was determined to be much lower quality than the devices you were trying to measure? Is this still the same ADC?

 

[pkane]

Making me wonder why even more why I hadn't seen mention before....must be slippin'

REW is excellent for this type of stuff.

 

[Pdxwayne]

I suspect the ADC, since both DACs should show much better performance than this. Didn't we go through these tests with you a while back where the ADC was determined to be much lower quality than the devices you were trying to measure? Is this still the same ADC?

I think that was the Beringer UCA202? It is Junk!
I just got it out and check its own loopback and it can't even get a flat freq response. Also, noise floor is like 30db.

Now I am using Focurite Scarlett Solo 3rd Gen. It would at least show flat freq response from X16. However, the noise floor seems to raise with freq. Can get up to 15db of noise floor near 20khz.

May I know what ADC you use? What is the noise floor? Maybe I should get a better one....

Thanks!

 

[pkane]

I think that was the Beringer UCA202? It is Junk!
I just got it out and check its own loopback and it can't even get a flat freq response. Also, noise floor is like 30db.
View attachment 139967

Now I am using Focurite Scarlett Solo 3rd Gen. It would at least show flat freq response from X16. However, the noise floor seems to raise with freq. Can get up to 15db of noise floor near 20khz.
View attachment 139968

May I know what ADC you use? What is the noise floor? Maybe I should get a better one....

Thanks!

I'm using various pro interfaces. Some I used recently: Focusrite Forte, Apogee Element, RME ADI-2 Pro FS.

 

[Pdxwayne]

I'm using various pro interfaces. Some I used recently: Focusrite Forte, Apogee Element, RME ADI-2 Pro FS.

Thanks!

By any chance you have the REW noise floor information for some of your interfaces?

Any favorite?

Thanks again!

 

[Blumlein 88]

Thanks!

By any chance you have the REW noise floor information for some of your interfaces?

Any favorite?

Thanks again!

Some he did even using REW which is convenient. Keep in mind different sized FFT's mean you have to adjust the noise level to make it a fair comparison. I think you were using 32 K FFTs and Paul is using 256 k FFTs in his measurements. So base level noise will show 9 db lower in Paul's measurements even if the noise level is the same vs 32 K FFT's.
https://www.audiosciencereview.com/...hunderbolt-interface-quick-measurements.7522/

 

[Pdxwayne]

Some he did even using REW which is convenient. Keep in mind different sized FFT's mean you have to adjust the noise level to make it a fair comparison. I think you were using 32 K FFTs and Paul is using 256 k FFTs in his measurements. So base level noise will show 9 db lower in Paul's measurements even if the noise level is the same vs 32 K FFT's.
https://www.audiosciencereview.com/...hunderbolt-interface-quick-measurements.7522/

Wow, very clean.

I am tempted to get a used one from
https://www.guitarcenter.com/Used/A...L632VxzyoONdNVVir542zILdu8wFpcHMaAhpLEALw_wcB

: )

But I don't have Apple computer....

 

[Pdxwayne]

Some he did even using REW which is convenient. Keep in mind different sized FFT's mean you have to adjust the noise level to make it a fair comparison. I think you were using 32 K FFTs and Paul is using 256 k FFTs in his measurements. So base level noise will show 9 db lower in Paul's measurements even if the noise level is the same vs 32 K FFT's.
https://www.audiosciencereview.com/...hunderbolt-interface-quick-measurements.7522/

BTW, all I need now is a great USB ADC... Are there any ~$500, as good as Apogee Element, usb based ADC that is Windows compatible?

Thanks!

 

[pkane]

BTW, all I need now is a great USB ADC... Are there any ~$500, as good as Apogee Element, usb based ADC that is Windows compatible?

Thanks!

There's been many discussions on this topic. Use search and the review index. Here's one such thread:

https://www.audiosciencereview.com/...or-distortion-measurements.24352/#post-822157

A used Focusrite Forte would be a good start. It has some noise that shows up around 37kHz, so it's better to measure at 48kHz or 44.1kHz. Used these can be had for around $200. Some measurements:

https://archimago.blogspot.com/2016/07/measurements-focusrite-forte-usb-audio.html

 

[Jimbob54]

There's been many discussions on this topic. Use search and the review index. Here's one such thread:

https://www.audiosciencereview.com/...or-distortion-measurements.24352/#post-822157

A used Focusrite Forte would be a good start. It has some noise that shows up around 37kHz, so it's better to measure at 48kHz or 44.1kHz. Used these can be had for around $200. Some measurements:

https://archimago.blogspot.com/2016/07/measurements-focusrite-forte-usb-audio.html

Or even better, he can get an RME ADI Pro and use it as his main DAC as well, have the best of both worlds and never worry again. Peace of mind comes at a price though!

 

[pkane]

Or even better, he can get an RME ADI Pro and use it as his main DAC as well, have the best of both worlds and never worry again. Peace of mind comes at a price though!

I was attempting to stay under the $500 budget, but sure, ADI Pro is a great device for measurements and for enjoying music

 

[Pdxwayne]

There's been many discussions on this topic. Use search and the review index. Here's one such thread:

https://www.audiosciencereview.com/...or-distortion-measurements.24352/#post-822157

A used Focusrite Forte would be a good start. It has some noise that shows up around 37kHz, so it's better to measure at 48kHz or 44.1kHz. Used these can be had for around $200. Some measurements:

https://archimago.blogspot.com/2016/07/measurements-focusrite-forte-usb-audio.html

Thanks for saving me the time to search and read!

: )

 

[Pdxwayne]

Or even better, he can get an RME ADI Pro and use it as his main DAC as well, have the best of both worlds and never worry again. Peace of mind comes at a price though!

I already have KTB, E30, X16, and d30pro as DAC. I wish to pay for just ADC and skip paying for DAC if possible. : )

RME ADI Pro sure looks great! But I am happy to go with just a used Focusrite Forte for 10% of the price.

 

[bravomail]

I am thinking that certain minor difference due to harmonics, filter, etc, could exhibit itself via very minor sound pressure difference. This thinking is based on my prior two DAC vs DAC blinds tests measurements.

In this particular case, I don't know where else to check as filter looks good, channel balance is within 0.05db, and tones check comparisons look fine other than 3khz. Thus I ask for suggestions here.

Try playing with filters of D30pro, if there's an option and choose the one u like.
I did my playing with filters on E30 - they do make audible difference.

 

[Pdxwayne]

Try playing with filters of D30pro, if there's an option and choose the one u like.
I did my playing with filters on E30 - they do make audible difference.

Thanks! I have yet to try other filters as filter 9 was suggested by JohnYoung of Topping. I have been using filter 9 since I got it.

I will try measure them with REW.

I will also try different filters with my living room stereo setup this weekend.

 

[Pdxwayne]

@pkane, I tried using node2i to play WAV file from USB drive, node2i coaxial to DAC, DAC to ADC, then back to laptop using Audacity to capture. I tried two different Windows 10 laptops and I got very disappointing results for both.

One I got null of like -55db. The other was like -30.

Would you please share your exact chain when doing DAC captures?

For example:
Computer hardware
Computer OS
Playback software
Capture software
Etc, etc

Thanks!

 

[pkane]

@pkane, I tried using node2i to play WAV file from USB drive, node2i coaxial to DAC, DAC to ADC, then back to laptop using Audacity to capture. I tried two different Windows 10 laptops and I got very disappointing results for both.

One I got null of like -55db. The other was like -30.

Would you please share your exact chain when doing DAC captures?

For example:
Computer hardware
Computer OS
Playback software
Capture software
Etc, etc

Thanks!

What ADC are you using?