Revisiting some "old" ideas from 1970's - IPS, OPS

I have the Delta 1010. I know it only does 96khz but do we really need higher for measuring audio?

Thanks, Terry

This one looks good. 192KHz is mostly required for good measurement of THD at 20KHz (harmonics are 40, 60, 80, etc. KHz).
Also, self-distortion of the card is important. My card shows external analog loop THD = 0.0001%
M-audio with 0.00072% THD+N is not bad at all. Although - it would be interesting to measure the external loop distortion at, say, 1, 10, 20 KHz.
 
This one looks good. 192KHz is mostly required for good measurement of THD at 20KHz (harmonics are 40, 60, 80, etc. KHz).
Also, self-distortion of the card is important. My card shows external analog loop THD = 0.0001%
M-audio with 0.00072% THD+N is not bad at all. Although - it would be interesting to measure the external loop distortion at, say, 1, 10, 20 KHz.

Good to hear. This is still just a hobby for me and the building is my favorite part although the testing is interesting and fun as well. I still need to buy a new tower so I likely won't be buying a different sound card anytime soon. I will buy the software.

Thanks again, Terry
 
Good to hear. This is still just a hobby for me and the building is my favorite part although the testing is interesting and fun as well. I still need to buy a new tower so I likely won't be buying a different sound card anytime soon. I will buy the software.

Thanks again, Terry

Cool - it will give you an ability to see some objective differences between the designs in terms of spectrums, harmonic profiles, THD / IMD levels, MLS multi-tone signal handling.

Make sure the ASIO driver is in place for the card - it gives the best possible precision in measurements.
 
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I need a laptop compatible USB card and was looking at Scarlett solo 2nd gen. It supports 192k with ASIO driver. Limitation might be how clean is psu when powered via USB. Although internal cards are at mercy of AT switching supply.

Is this good enough or do I need one with independent power supply?

Solo 2nd gen:
https://www.amazon.com/gp/aw/d/B01E6T56CM/
 
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You guys don't have issues with the ADC/DAC card being connected to a noisy PC bus and powered by a noisy PC power supply? I know there are guys working to use complex shunt regulated PSU's for their DACs to get noise/ripple below 50uV etc. I have a cheap USB powered DAC and can hear the noise vs when I use a DAC powered with a clean toroidal and filtered and regulated even with a 7805.

They must have some good noise suppression on those sound cards.
 
You guys don't have issues with the ADC/DAC card being connected to a noisy PC bus and powered by a noisy PC power supply? I know there are guys working to use complex shunt regulated PSU's for their DACs to get noise/ripple below 50uV etc. I have a cheap USB powered DAC and can hear the noise vs when I use a DAC powered with a clean toroidal and filtered and regulated even with a 7805.

They must have some good noise suppression on those sound cards.

I believe my card is equipped with a good regulator, plus it's got balanced inputs / outputs.
If there's no some ground loop, arranged by me :)p), it's very quiet, even if I use only one side of the balanced input.
 
We had a request for making sure NS Modular runs fine at 2 ohm load at low frequencies, so Jeff has quickly tested NS Modular + X4 VFA.
That's what he wrote after the test :D

"You've designed a tank! 595W (34.5V RMS) at clipping at 50Hz with 63V rails into 2 ohms. It didn't really even get that warm on a 10 second run. I ran it down at 30Hz also."

Pretty tough thing :smash: :eek: