This circuit was found in Radio Electronics from the 90s. The transducer is a tweeter and the power transistor must have a heatsink.
This circuit can be interleaved between guitars and guitars to give the fuzz distortion effect. The...
This 1969 Philips documentation circuit makes it possible to control an engine through the sound...
This circuit, suitable for tube equipment, was found in an old documentation. It uses a high...