Custom Contact Mic Preamps
Piezo contact mics are a cheap and easy way to record some crazy sounds. However, if you just solder a piezo disc to a mic cable they will sound kind of bad. I use Zach Poff and Alex Rice’s circuit to build contact mics and preamps that sound really great, and I try to make them look nice too. Check out the photos below for a bunch of examples.
I build the preamps into little boxes that I find in charity shops and car boot sales (aka thrift stores and flea markets). They are phantom powered and use XLR in and out. You clamp the piezo mic onto whatever surface you want to record. The piezo connects to the preamp, and the preamp connects to whatever phantom-powered recorder you have. It sounds great on machinery (like sewing machines), unusual materials, fences, bridges, music boxes, upright bass, banjo, and more. The piezo mics can easily be made waterproof, creating an underwater microphone (or hydrophone).
If you have electronics skills I’d encourage you to make one yourself, using Zach’s tutorial. Or, please get in touch if you would like me to build you one. Depending on specifications, price for a single channel preamp and matching microphone starts at £150. Send me an email at email@example.com.
Here are a few recordings, more are on the way: