Substance drying as a feedback modulator by substance drying published on 2012-10-26T21:03:57Z Several microphones are placed in contact with different speaker cones, immersed in an hardening substance. As it gets harder it modulates the resulting feedback until it dries completely. Different substances - glues, plaster, epoxies, silicone, paint - with their distinctive densities and drying times will have diverse influences on the resulting sound. The characteristics of the different speakers cones will also affect the final result. the piece ends when all materials are dry and there is no more change to the sound. the substances used here were contact glue, wall filler, quick drying wood glue, epoxy and normal white glue.