> A variation on this is used to check the authenticity of some > recordings in forensic audio. Almost all 'surveillance' audio > contains some low level 50/60 Hz. If the recording is done on > a digital device then its clock can be assumed to be more stable > than the mains frequency At least in NA, mains frequency is very very stable. The entire continent is in phase and clocked with very high precision. It's more stable than a free-running digital clock. ...I used this fact to 'cheat' in a high school physics contest where we had to build a clock and the winner was the most stable. Ours had a CdS cell that watched the 120Hz flicker of the lights in the room. Monty _______________________________________________ Linux-audio-user mailing list Linux-audio-user@xxxxxxxxxxxxxxxxxxxx http://lists.linuxaudio.org/listinfo/linux-audio-user
