I have your temperature control board glued to the ADC chip, so I think I'm OK after a half hour warmup. But, that's a good point.don't forget to warm up the ADC, even with a hairdryer, ES9822 has a minimal H3 at about 50C.
It is not always so. I have very average audio system with inexpensive china DAC, DIY D class amplifier and 3-way Speakers 150 Watt power and 91 dB sensitivity. I am 56 years old. But i can hear the 3 kHz 96/24 signal, which I turn on/off using the play/pause button on the player. From a listening position of 2m with an attenuation of -105dBFS. And of 1 cm from the speaker with a level of -128 dBFS. Although, of course, this has no effect on my emotions from listening to old noisy music .It stays right at about -120 dBc. That's consistent across sample rates, ADC attenuator settings, and any DAC output level within a dB or two of dBFS. I'm certain that level can't be heard in the very best of audio systems by the most sensitive of ears, especially with actual music, but it sure can be measured.
Yep, switching to Blackman-Harris 7 certainly improves things! (I should have remembered that Rectangular window only works when the input and output devices have a common clock. Cool that REW even detects the clock delta here!) Thanks!
So, which one is right?
I would repeat the measurement with A: the APU's notch filter set to +6dB and B: the ADC set to 1.7VI think this one shows the correct D10s performance:
Although it is possible to make them go away with DSD output, so I reckon a bit of shaped dither may be worth a shot...There is a difference between ESS and AKM. If you lower the input level on an AKM ADC to -20 dBFS, all harmonics are gone. If you do this on an ESS, harmonics and spurious tones stay, and you need to go down to at least -60 dB to get rid of them.
Well, yes, I was thinking more of the DAC side... what you were describing is nothing less than the venerable "ESS hump". Here's an example:I don't see how this relates to using an ADC. Or how to add shaped dither to a DSD signal.
Doing some more research this is what I have been able to find:Is there a schematic of the frontend of Cosmos ADC somewhere, or some other way to see what kind of input protection there is, if any? I'm wondering how careful I have to be to avoid overvoltage. I don't want to break this thing!
I would repeat the measurement with A: the APU's notch filter set to +6dB and B: the ADC set to 1.7V
With the D10s set to 0dBFS, that should give you an amplitude of roughly -3.16dBFS in REW.
The closer you can get the input to -.5dBFS, the further away the ADC's noise floor is from your point of interest, the more accurate your measurements will be.
Are you sure that your D10s is playing at 0dBFS?Now, ADC sensitivity at 1.7 Vrms:
I can't match arvidb's distortion nor can I get to Amir or L7's noise level. Bad karma, probably.