Based on the Warden optical compressor, the SQWZR is a studio-grade guitar and bass compressor with high headroom.
It is a very quiet compressor with a very useful "Tone" control. Use "Attack" and "Release" to shape the speed of the effect. Set "Ratio" to maximum if you want a more compressed signal. "Sustain" controls the pre-compressor gain, while "Level" is the overall output.
Current draw: 13 mA
Voltage: 9 Vdc only. Anything higher will blow some capacitors.