Now available from Tronixabs Australia is the fascinating MSGEQ7 audio analyser IC on a convenient breakout board. The MSGEQ7 breaks down sound into seven frequency bands, and reports the peak level for each band using an analogue output. The seven bands are
This module features the MSGEQ7 graphic equalizer display filter.It will give your arduino ears. Sound is broken down into seven frequency bands and the peak level for each band can be read. The MSGEQ7 will return the strengths of the audio at seven points – 63 Hz, 160 Hz, 400 Hz, 1 kHz, 2.5 kHz, 6.25 kHz and 16 kHz - for example:
The board requires 5V to operate. You can see some example projects on John's tronixstuff personal website.