I know this is a dangerous precedent, but I was listening to Andrew last week, and he mentioned that if you take a piezo electric transducer (PZT), wire it up as a contact mic, connect it to a recorder and turn up the volume, then they can be noisy in a musical way.
I found this interesting as I have made contact mics from time to time, and had not noticed the background noise particularly, so I decided to have a look at this, to see if there is a way of reinforcing this aspect of the output.
This confection is a PZT which I stripped of a plastic protecting ring, and soldered up to an unbalanced mono audio jack lead. The springs are extended, to partially isolate the PZT, and to apply some stress to the PZT to trigger the cell. The pins are hammered into a solo rhythm stick, and the soldered lead is taped to the stick to support the joints.
When connected up to a mini amp, the mic is quiet until the springs start to ring, after which the circuit will start to feedback. It is possible that the stripped PZT could be used as a cheap replacement to a microphone in surveillance systems where the presence of a noise is required to trigger the attention of a video system.
Ru
No comments:
Post a Comment