How do I convert an old pair of headphones into a microphone?

So I'm trying to convert a vintage pair of over-the-ear headphones into a microphone (using only one of the earpieces obviously) and I'm not sure how to re-wire it after I went and disconnected the 2nd earpiece.

Basic info: The remaining earpiece has a tone knob, volume knob, and a mono/stereo toggle switch. It has a 1/4" cord compromised of positive, negative, and a ground. It's a 0.3W 8ohm speaker.

I got the idea for this after seeing an old telephone converted into a microphone and I've been wanting to get a lo-fi sounding mic for a while now and figured I'd save some cash by recycling these old things.

rickharris5 years ago
You have one of 2 things there:

1. A magnetic head phone - Effectively a small speaker
2. A crystal head phone - A pizeo crystal connected to a cone.


Taking wires from the 2 connections on the actual head phone module to an amplifier should work OK - Forget the tone vol etc.

The quality WILL be poor. lots of high freq and little at the low end.

An old telephone would have a carbon mike - A container with carbon granules in it - When they get shaken about by your voice they change the voltage across them - This requires a battery in series with the mike.
+1 about the quality! It will be terrible!
canucksgirl5 years ago
How and where do you intend to use the new "microphone"? I know that in a pinch, plugging headphones into a PC microphone port, and then adjusting the settings on your computer for "sound recording" and upping the volume will allow speakers to work as a microphone. This of course doesn't require any rewiring.