How do you get loopback with ASIO digital on the output and analog balanced on the input???
You can't get the same measurement from APx555 since its DAC is not as good as okto.
Looks like you are confusing the performance of AP when it is producing digital samples (which is as perfect as it can get) versus using its analog generator. The former is essentially noise-free to -140 dB.
I meant same input condition.
Yesterday I measured AP's output noise with my 40dB noise amplifier at minimum output level that still has an output about 30nV iirc. So I assumed it wouldn't change with levels. But it may actually change. The output noise is 0.18uV much lower than the input of 0.85uV at 310mV range.
The way to test the noise at higher level is to set output higher than 20khz and use external low pass to remove the tone to crush the amplitude. Then put it through the 40dB amplifier. I'll try that later.
What it shows is possibly that the noise of DAC8 stereo is lower than AP's output. But it's that the dynamic range is not that high (only 127dB) made me confused. The input equivalent noise at 5V range is about 5uV so the dynamic range number should always be higher than dashboard so no issue there.