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Evaluating AD/DA loops by means of Audio Diffmaker
Old 18th November 2022 | Show parent
  #2641
Gear Head
 
Quote:
Originally Posted by TJ99 ➡️
Yes, but they are there for a reason, I suppose? Isn't there the possibilty that a DC signal interferes with the AC signal, resulting in measureable and even audible noise (or something similar)?
DC in an audio signal causes a loss of headroom if nothing else. It's not great for speakers either. Having the cone at a constant offset can cause distortion or in the worst case damage the voice coil.
Old 19th November 2022 | Show parent
  #2642
Gear Addict
 
🎧 5 years
Quote:
Originally Posted by demarcus_b ➡️
DC in an audio signal causes a loss of headroom if nothing else. It's not great for speakers either. Having the cone at a constant offset can cause distortion or in the worst case damage the voice coil.
Thanks for clearing that up. So bypassing them doesn't seem to be a good idea after all, as I thought.
Old 19th November 2022 | Show parent
  #2643
Gear Nut
 
Quote:
Originally Posted by TJ99 ➡️
Thanks for clearing that up. So bypassing them doesn't seem to be a good idea after all, as I thought.
I imagined in certain scenarios when you are mastering doing a loop back and you know that there is no dc in the signal that by passing any filters may reduce possible phase shift caused by the hp
Old 19th November 2022 | Show parent
  #2644
Lives for gear
 
johannburkard's Avatar
Quote:
Originally Posted by TJ99 ➡️
Thanks for clearing that up. So bypassing them doesn't seem to be a good idea after all, as I thought.
Are you mastering direct from your A/D? In my mind, everybody has some digital processing coming after it, for example a high-pass filter. Or, ahem, a limiter?
Old 9th December 2022 | Show parent
  #2645
Lives for gear
 
🎧 15 years
Hoping someone with an IZ Radar (classic, ultra,... ) can contribute to this test.
Old 9th December 2022
  #2646
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didier.brest's Avatar
 
🎧 10 years
Test of the Behringer Wing by loicm from French audio forum Audiofanzine:
aux out to aux in: 601.49 µs, -0.1594 dB (L), -0.1398 dB (R), -53.9 dBFS (L), -54.9 dBFS (R)
xlr out to aux in: 634.74 µs, 0.9 dB (L), 0.9 dB (R), -48.3 dBFS (L), -49.9 dBFS (R)
aux out to xlr in: 599.24 µs, 0.6 dB (L), 0.6 dB (R), -39.5 dBFS (L), -41.1 dBFS (R)
xlr out to xlr in: 633.24 µs, 0.3 dB (L), 0.3 dB (R), -39.4 dBFS (L), -41.2 dBFS (R)

To be added to the next issue of the list of the results.

Last edited by didier.brest; 11th December 2022 at 09:17 PM..
Old 11th December 2022
  #2647
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didier.brest's Avatar
 
🎧 10 years
Test of the Midas DL 16, xlr i/o, driven by the Behringer Wing as master clock through AES50 by loicm from the French forum Audiofanzine::
436.34 µs, 0.4177 dB (L), 0.3888 dB (R), -39.4 dBFS (L), -41.1446 dBFS (R)

To be added to the next issue of the list of the results.

Loopback tests requested by forum members: Eventide H8000FW and Eventide H9000R (for confirming the ones at the top of the list of the results), Pacific Microsonics Model One and Model Two, Slate Digital VRS-8, SSL 2+, RME M-32 AD Pro --> M-32 DA Pro, RME M-1610 Pro, Audient iD14 MKII, Prism Dream DA-2 --> AD-2, BlackLion Audio Revolution 2×2, RME MADIface Pro, RME Fireface UCX II, SSL BiG SiX, Prism Sound Dream ADA-128, anything from Qes Lab, JCF, Burl and Linn, PreSonus Quantum 2626, PreSonus Studio 192, iZ RADAR. Of course any other one welcome!

Last edited by didier.brest; 3 weeks ago at 02:09 PM..
Old 12th December 2022
  #2648
Here for the gear
 
Hello,

Rode AI-1, L+R monitor out to xlr/combo IN

https://www.mediafire.com/file/4y3r6...DEAI1.wav/file

PD: It would be great if someone with an Avid Omni could contribute to the test.
Old 12th December 2022 | Show parent
  #2649
Lives for gear
 
didier.brest's Avatar
 
🎧 10 years
Quote:
Originally Posted by faronorte ➡️
Rode AI-1, L+R monitor out to xlr/combo IN
Rode AI-1 has a single XLR-1/4" combo input. Did you do separate records for the L and R channels ?

-8.932646 ms, 0.5916 dB (L), 0.5390 dB (R), -33.4775 dBFS (L), -31.6123 dBFS (R)
Old 13th December 2022 | Show parent
  #2650
Here for the gear
 
Quote:
Originally Posted by didier.brest ➡️
Rode AI-1 has a single XLR-1/4" combo input. Did you do separate records for the L and R channels ?

-8.932646 ms, 0.5916 dB (L), 0.5390 dB (R), -33.4775 dBFS (L), -31.6123 dBFS (R)
Yes, I recorded the L and R channels separately and then put them together in the stereo file.
Old 13th December 2022 | Show parent
  #2651
Lives for gear
 
didier.brest's Avatar
 
🎧 10 years
That's fine. It might have jeopardized the joint L and R measurement if the L and R delays would have been too much different but they are not.
L and R channels measured separately:
L channel: -8.933157 ms, 0.5917 dB, -33.4794 dBFS
R channel: -8.932646 ms, 0.5390 dB, -31.6123 dBFS

To be added to the next issue of the list of the results.

Loopback tests requested by forum members: Eventide H8000FW and Eventide H9000R (for confirming the ones at the top of the list of the results), Pacific Microsonics Model One and Model Two, Slate Digital VRS-8, SSL 2+, RME M-32 AD Pro --> M-32 DA Pro, RME M-1610 Pro, Audient iD14 MKII, Prism Dream DA-2 --> AD-2, BlackLion Audio Revolution 2×2, RME MADIface Pro, RME Fireface UCX II, SSL BiG SiX, Prism Sound Dream ADA-128, anything from Qes Lab, JCF, Burl and Linn, PreSonus Quantum 2626, PreSonus Studio 192, iZ RADAR, Avid HD OMNI. Of course any other one welcome!
Old 17th December 2022
  #2652
Lives for gear
Request Axe-FX III.
Old 17th December 2022 | Show parent
  #2653
Lives for gear
Quote:
Originally Posted by living sounds ➡️
Modern AD chips typically employ a highpass filter in the digital realm, so bridging caps won't help there.

There are chips like the PCM4222 that allow you to turn the filter off, but the resulting DC requires DC offset adjustment in the analog domain to get it down to levels that today would be viewed as acceptable. This would also demand a calibration procedure to be run continuously.

The now-discontinued Prism AD-2 seems to have used something like a DC servo to constantly adjust DC.

To my ears the digital filters, despite being nominally outside the hearing range, quite obviously alter the sound. Whenever possible I opt to go without them. For some reason they are a lot worse than simple DC blocking caps in a well-designed analog signal path.
Can someone explain why this would be necessary? Is this because it would eventually pass some DC non-sense to your monitors? And if so, could you not just run a limiter and or peak detection in your software?

If you were ultimately just using this to track audio, what do you need the DC coupling for?
Old 18th December 2022
  #2654
Lives for gear
Request Cranborne 500R8.
Old 24th December 2022 | Show parent
  #2655
Lives for gear
 
🎧 15 years
RME ADI-2 PRO FS R BE; AD FILTER = SHARP; DC FILTER = NONE

https://drive.google.com/drive/folde...usp=share_link
Old 25th December 2022 | Show parent
  #2656
Old 25th December 2022 | Show parent
  #2657
Lives for gear
 
didier.brest's Avatar
 
🎧 10 years
Quote:
Originally Posted by Diegel ➡️
RME ADI-2 PRO FS R BE; AD FILTER = SHARP; DC FILTER = NONE
1.2045420 ms, 0.0761 dB (L), 0.0782 dB (R), -37.8864 dBFS (L), -39.1733 dBFS (R)

This is not in agreement with previous results from ADI-2 Pro in the list of the results.

Last edited by didier.brest; 4 weeks ago at 06:57 PM..
Old 25th December 2022 | Show parent
  #2658
Lives for gear
 
didier.brest's Avatar
 
🎧 10 years
Quote:
Originally Posted by Diegel ➡️
Lynx Aurora (n)
-779 ns, -0.0117 dB (L), -0.0098 dBFS (R), -58.8982 dBFS (L), -59.0200 dBFS (R)

To be added to the next issue of the list of the results.

Loopback tests requested by forum members: Eventide H8000FW and Eventide H9000R (for confirming the ones at the top of the list of the results), Pacific Microsonics Model One and Model Two, Slate Digital VRS-8, SSL 2+, RME M-32 AD Pro --> M-32 DA Pro, RME M-1610 Pro, Audient iD14 MKII, Prism Dream DA-2 --> AD-2, BlackLion Audio Revolution 2×2, RME MADIface Pro, RME Fireface UCX II, SSL BiG SiX, Prism Sound Dream ADA-128, anything from Qes Lab, JCF, Burl and Linn, PreSonus Quantum 2626, PreSonus Studio 192, iZ RADAR, Avid HD OMNI, Cranborne Audio 500R8. Of course any other one welcome!
Old 26th December 2022 | Show parent
  #2659
Lives for gear
 
🎧 15 years
Quote:
Originally Posted by didier.brest ➡️
1.2045420 ms, 0.0761 dB (L), 0.0782 dB (R), -37.8864 dBFS (L), -39.1733 dBFS (R)

This is not in agreement with previous results from ADI-2 P in the list of the results.
I also noticed it was performing significantly worse than my lynx in another loopback test. And this is the 2nd unit I had and both performed similarly. Not sure what the issue is? If anyone with the Rme can point out some things to check that would be much appreciated.
Old 26th December 2022 | Show parent
  #2660
Lives for gear
 
🎧 15 years
RME ADI-2 PRO FS R BE; AD FILTER = SD SHARP; DC FILTER = NONE

https://drive.google.com/drive/folde...usp=share_link
Old 26th December 2022 | Show parent
  #2661
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didier.brest's Avatar
 
🎧 10 years
Quote:
Originally Posted by Diegel ➡️
RME ADI-2 PRO FS R BE; AD FILTER = SD SHARP; DC FILTER = NONE
1.519764 ms, 0.0714 dB (L), 0.0750 dB (R), -37.4386 dBFS (L), -38.7250 dBFS (R)
Old 26th December 2022 | Show parent
  #2662
Gear Addict
 
🎧 5 years
Quote:
Originally Posted by Diegel ➡️
I also noticed it was performing significantly worse than my lynx in another loopback test. And this is the 2nd unit I had and both performed similarly. Not sure what the issue is? If anyone with the Rme can point out some things to check that would be much appreciated.
Are you using the same cables for both measurements?
Old 26th December 2022 | Show parent
  #2663
Lives for gear
 
🎧 15 years
Quote:
Originally Posted by TJ99 ➡️
Are you using the same cables for both measurements?
Yep. I’m gonna try again physically moving the rme at least 2 feet away from any equipment. Not sure what else to try. I made sure no eq was on.
Old 27th December 2022 | Show parent
  #2664
Gear Addict
 
🎧 5 years
Quote:
Originally Posted by Diegel ➡️
Yep. I’m gonna try again physically moving the rme at least 2 feet away from any equipment. Not sure what else to try. I made sure no eq was on.
If nothing helps, try contacting RME support. I heard they usually are helpful and answer immediately.
Old 27th December 2022 | Show parent
  #2665
Gear Head
 
Quote:
Originally Posted by Diegel ➡️
Yep. I’m gonna try again physically moving the rme at least 2 feet away from any equipment. Not sure what else to try. I made sure no eq was on.
Double check that the DC filter is really turned off. It appears to be turned on. Besides this, the result is still worse than similar RME devices with the same settings, so something else is likely misconfigured. Considering the many hundreds of combinations of various settings that are possible, that's not that unusual.
Old 27th December 2022 | Show parent
  #2666
Lives for gear
 
🎧 15 years
DC filter is 100% off. I also tried changing cables, plugging the power directly to the wall (instead of power conditioner) and moved it at least 3 feet from any equipment. Getting virtually identical result. Will try calling rme later.
Attached Thumbnails
Evaluating AD/DA loops by means of Audio Diffmaker-img_3786.jpg  
Old 27th December 2022 | Show parent
  #2667
Gear Head
 
Quote:
Originally Posted by Diegel ➡️
DC filter is 100% off. I also tried changing cables, plugging the power directly to the wall (instead of power conditioner) and moved it at least 3 feet from any equipment. Getting virtually identical result. Will try calling rme later.
Here's why I think your DC filter is still engaged. This is from your original file:

Evaluating AD/DA loops by means of Audio Diffmaker-filter.png

And here's my ADI-2 Pro FS with the DC filter off:

Evaluating AD/DA loops by means of Audio Diffmaker-nofilter.png
Attached Thumbnails
Evaluating AD/DA loops by means of Audio Diffmaker-nofilter.png   Evaluating AD/DA loops by means of Audio Diffmaker-filter.png  
Old 27th December 2022
  #2668
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Lumbergh's Avatar
 
🎧 5 years
looks like a bug, does ADI-2 have firmware updates?
Old 27th December 2022 | Show parent
  #2669
Lives for gear
 
🎧 15 years
Quote:
Originally Posted by Lumbergh ➡️
looks like a bug, does ADI-2 have firmware updates?
I did the firmware update prior to the tests. Also total mix didnt seem to install and does not open when the rme is connected. Maybe that has something to do with issue.
Old 27th December 2022 | Show parent
  #2670
Gear Head
 
Quote:
Originally Posted by Diegel ➡️
I did the firmware update prior to the tests. Also total mix didnt seem to install and does not open when the rme is connected. Maybe that has something to do with issue.
I'd try to reapply the firmware update, just to be sure, with a fresh download of the latest from RME forums.
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