Ok, our Aliexpress has ADCiso grade B for $179.Well, I've ordered a Cosmos ADC Grade B + the Hifime isolator now, so in a week or so we'll know if it works or not! Cost (including shipping for the isolator and 25 % VAT): €305, compared to €343 for the Cosmos ADCiso (Grade A?) only. (From Audiophonics.)
@IVX , To be honest, since I purchased Cosmos Scaler as an input buffer, I overlooked the gain feature that gives Scaler its name. I compared DR tests.Thank you, pls try to compare DR(THD+N@1kHz -60dbfs A-weighted) tests, ADC vs ADC+Scaler(gain +20..+26db). ADC+Scaler outerforms APx555b for 7db in the DR test of Meizu HiFi DAC.
No specific reason. I just chose one of +20..+26db gains to check the effect. Attached is the measurement of +26.078 gain.What was the reason to use 25.527 dB gain instead of 26.078?
@IVX, Thank you for pointing this out. I used the AW calibration file this time. Is this A-weighted now?oal, if you want to see the THD+N results A-weighted online, without extra calculations, please try AW calibration file for REW.
BTW, I see your DR is 134db(A) with Scaler, that's actually so-so for 4x DACs with 130db(A)* of each, where is 136db(A) expected.
* Cirrus competitors told me that Cirrus cheated with DR in their cs43131/198 i.e. DAC switches its gain at about -20dbfs level, and deceives DR test but 0dbfs exhibits the DAC has real DR about 118-120db(A).
Perhaps my too-good-to-be-true results are due to the cheating.Ok, I thought I've missed something important about these gain levels, as I used +26 dB for -60 dB signal to measure my ADI-2 but results were not so spectacular.
Thank You,misureaudio, I testing Cosmos ADC twice, the first time I marking the PCB A; B; 0. Next, I test the unit after assembling, sometimes B marked unit becomes A.
remember, the cheating isn't proved technical way and came from the competitor's side. What we can see is -130db(A) noise/130db(A) DR from a tiny and cheap DAC with ridiculously low power consumption for such a noise level(550nVrms(A)). On the other hand, THD+N is -115db at 0dbfs i.e. typical for such cheap and low-power DAC.Perhaps my too-good-to-be-true results are due to the cheating.