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Cosmos APU a notch+LNA $70 to outperform APx555b for $30,000

I found my screenshots of the very best Cosmos ADC THD performance from 2022. I sold that unit to Capslock member but no idea where is it now.
ES9822 average H3 is around -137db at 1kHz -.5dbfs, the worst was -133-134db.
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The second LPF version proto is tested. H2 performance(-150db is a good result for SE) and noise were improved for SE outputs. Now SE loses less than 1db of the original 9039S THD+N, -125.2db/125.8db.

9039S->LPF at the Left SE output 4.6Vrms, APU +6db, that test shows the THD+N(<-128db) performance for SE applications.

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The same test, but APU 0db, to show the THD performance of SE applications.

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9039S->SE Left 3.5V APU 0db, THD test. Ultra-high performance balance/unbalance converter, due to highly symmetrical structure and delicate PCB layout full 9039S performance translated to the unbalanced output with virtually no losses. BTW, 100mA outputs may drive headphones.
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The same test but APU 6db, THD+N performance test.
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9039S->SE Right 3.5V APU 0db, THD test.
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The same test but APU 6db, THD+N performance test.

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9039S->LPF balanced output 4.6Vrms, THD performance test, close to -155db, all harmonics about -160db or less.

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9039S->LPF balanced output 7.75Vrms, THD+N performance test, less than -131db(limited by APU).

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I had hoped that the Bal2Ubal stage of Cosmos LPF could produce a nearly ideal IMD test stimulus. For that reason, I added one more dip-switch poles(9 and 10) to connect the same stage to both the Left and Right DAC's outputs, so the differential amp works as a mixer of 2 freqs. However, I see pretty much the same IMD performance as 9039S tied with no mixer to the Cosmos ADCiso with 1ord HPF(22nF in serial right in the cable).
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That should be very nice. Maybe you could even add a common clock.

The only thing I'd be concerned about is whether you'd get ground loops between them already. All of them contain DC/DC converters, but only the ADCiso has one that offers galvanic isolation. so you'd have a double ground path into all of the other components. Balanced signalling should take care of most of the common mode stuff but not necessarily at the frequencies the converters operate at.