The Idea
A vinyl record that obeys both rules: it sounds like music when you play it through a turntable, and it draws a picture when you play it through a fax decoder. The audio waveform is engineered to be dual-purpose. Pleasing to the ear and legible as image data when decoded through the right system.
The Reference
Aphex Twin's "Equation" hides a face in the spectrogram of the song. SSTV. Slow-scan television, used in amateur radio for decades. Transmits still images via audio frequencies. So the precedent for "audio as image" is real, not hypothetical. The record just makes it the point of the piece.
The Form
Could be a single object. A record paired with a fax printer that produces the artwork at playback. Could be a series, each record carrying a different hidden image. Could be a performance: play the record live, watch the image emerge from the printer in real time, frame by frame, while the music plays.
Status
Concept.