iPod Touch Audio Glitch
July 18, 2009 – 12:31 pm by John Keston
Lately I’ve been experimenting with iPod Touch applications for recording sound. Generally it’s necessary to use a headset to make a recording, but my goal is to figure out a practical way to bypass the headset with an input for a high quality microphone. While unsuccessfully testing my Audio Technica AT822 stereo mic as an input for the iPod Touch I captured an interesting glitch within the application I was testing.
The low frequency waveform (shown in the image at the left) played at regular intervals while I had the microphone attached. Perhaps it’s some sort of communication protocol for headset controls. I removed the DC offset, but otherwise left it as it was. Perhaps I’ll try playing it back at some higher frequencies to see it’s useful for anything musically.