Haven't thought through all the details for different device categories. Thinking out loud, it would be kind of like this:
DAC:
Output level: Minimum of 2 volts for unbalanced, 4 volts for balanced.
SINAD: >= 110 dB
DNR: >= 115 dB
Jitter (all inputs): < -115 dB (in FFT spectrum)
Filter attenuation 44.1 kHz sampling at 24 kHz: better than -100 dB
Frequency Response flatness: Less than 0.2 dB @ 20 kHz
Don't know yet how to include responses for the sweeps such as IMD. And for multitone, need to do some research to see what is a reasonable minimum.
AVRs:
Output level: Minimum of (undistorted) 2 volts for unbalanced, 4 volts for balanced.
DAC section:
SINAD: AVRs, better than 95 dB. AVPs, better than 100 dB
DNR: >= 115 dB
Jitter (all inputs): < -115 dB (in FFT spectrum)
Filter attenuation 44.1 kHz sampling at 24 kHz: better than -100 dB
Frequency Response flatness: Less than 0.2 dB @ 20 kHz
Amplifier Section:
SINAD with digital or analog input > 80 dB
SNR: ???
You get the idea.