Cheap mass-market grotbox speakers reveal how a mix translates to the worst-case playback scenario

Grotboxes — cheap PC speakers, boomboxes, or similar consumer playback devices — deliberately expose resonance artifacts, limited frequency response, and non-linearity of real-world mass-market playback. Driving them loudly emphasizes distortion and resonance. The most useful configuration: two small speakers placed side by side (close together), which removes useful stereo information without electrically summing to mono — this is the worst-case scenario for central lead vocal and lead instrument audibility, making it the acid test of lyric intelligibility and vocal level. Placing grotboxes outside the studio room (listening from the hall or doorway) provides another perspective on mono/narrow-field playback that compensates for the engineer’s proximity bias.

Examples

Bob Clearmountain: ‘Those are actually my favorites! I have them placed right next to each other at the side of the room… They’re also good for setting vocal levels.‘

Assessment

Why does placing two small speakers side by side (rather than summing to mono electrically) create a worse test for vocal intelligibility than normal mono summing? What additional information do grotboxes provide that the Auratone substitute cannot?