Comment Re:60 Hz. hum in audio equipment (Score 1) 790
Actually the audible buzz from the speakers of most audio equipment is 100/120Hz due to full wave rectification which doubles the frequency. There are families of harmonics too.
A sound restoration area I'm involved with uses the mains hum present on old master recordings to determine the optimal playback speed.
A sound restoration area I'm involved with uses the mains hum present on old master recordings to determine the optimal playback speed.