If video uses color bars to test and align color values among TV sets, what could be the equivalent in Audio?
If you want the AI to relate to how we perceive sound, maybe something like

a linear chirp from 20Hz-20kHz
white noise in the same bandwidth
a single sine wave at 1kHz (roughly our greatest sensitivity)
a harmonic series from 55hz doubling up to 14.08kHz (all A notes to illustrate octaves)
other harmonic series and/or progression to illustrate important musical intervals (major and minor chords, pentatonic scale)
sound level variation of one or more of the above between 0dB SPL and some appropriate limit to establish dynamics

In terms of storage, a set of vectors is probably the best place to start. You can make one long vector with your test pattern and load it into and out of a WAV file I suppose.