fold down

fold down (third-person singular simple present folds down, present participle folding down, simple past and past participle folded down)

1. (transitive, audio) To downmix.
   • 2012, Hilary Wyatt, Tim Amyes, Audio Post Production for Television and Film:

     Folding down to mono can create problems if essential material has been recorded into the surrounds, as it will be lost.

• downfold