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Measuring audio Answered

I have a project where I need to be able to measure 3 or 4 microphones and decide which one is getting in the loudest input volume. In other words to know who is talking around a four persons table.

Does anyone have any idea how to solve this problem? I'm using arduino (http://www.arduino.cc/) for the rest of the project so I'm able to use the arduino to measure dc voltage but how do I transfer the sound wave into a measurable dc voltage?

thx in advance / david



11 years ago

And audio signal, once it is past the microphone, is just form of AC electricity that you can measure like any other AC signal. There's a standard circuit called a "peak detector" that converts the audio signal to a more-slowly changing DC signal that would be easy to read with a meter (this is what normally drives a VU meter on recording equipment), or could be read into a micro via an A-D converter. (a micro with an A-D converter could probably do the "peak detect" in software, but it hardly seems worth it.) One sample circuit I found is here:

So, are you going to tell us a little more about your project? If it has a preamp or if it's just into a microcontroller or what? We need to know more about your setup first, dude.

okay. My project is to create a table which is going to use 400-500 individually controlled leds. This is going to form a matrix of multicolored leds which will be controlled by the people sitting around the table talking via the microphones. The output of this hole project is going to be a ambient display showing a "fingerprint" of the conversation constantly changing and adopting to the sound scape around the table. The technology I will be using is pure Arduino (microcontroller) and nothing more. I will build my own dmx controller to controll the leds. Anything else u need to know?

from my limited knowledge of electronics (which may give you a place to research)... perhaps a transducer? or some sort of amplifier (even an audio amp).