This patch mixes two audio signals, then makes one disappear by reversing its phase. A similar method was used by U.S. military to encrypt radio transmissions during the 20th century. A phonograph record was the ‘key’ to unlock the encoded transmission. In practice it was difficult to synchronize the two recordings to achieve phase cancellation.
download
https://github.com/tkzic/max-projects
folder: phase-cancellation
patches:
- phase-cancellation-example.maxpat
- disappearing-act.maxpat