Contact microphones are amazing things – they pick up the vibrations of the material they are attached to, rather than the movement of air (like normal microphones). That means you can hear all sorts of wonderful things that you would normally be totally unaware of. Piezo discs are essentially cheap and easy contact microphones, but they have a well-deserved bad reputation for sounding pretty terrible if you just plug them into a recording machine. However, building a simple preamp is a really effective way of making even a lowly piezo microphone sound totally amazing.

So I recently built some new contact microphones and a phantom powered preamp, using Alex Rice’s technique as detailed on Zach Poff’s fantastic website.

I’ve always loved mechanical sounds, and my wife has been doing a lot of sewing lately. I was really excited to use my new microphones to make some recordings of her sewing machine in action.

Here are the recordings on their own, feel free to download them and play around. Each recording uses slightly different microphone placement, so you can hear the various differences in the machinery – also you can can varying levels of hum! Apologies for that, I think it’s partially down to the machinery and partially from my microphones, which need improved wiring.

Oh, and here’s a picture of the thing Kristina was sewing! You can read more about it on the Crafty Foxes blog…

And some pictures of the mics, and how they attached to the sewing machine. You can see them plugged directly into the cigar box preamp, which is then plugged into my RME Fireface audio interface.