I tested the circuit and it works good (this is a mine concept) the comparator can be an ua741 and the mosfet an irf3205 enjoy it. The circuit works good with a power supply of 22V<Voltage Supply<30V. I obtained best results at 24V. In the circuit you will have to replace the sine waveform generator with a jack from a music source (for example a phone). Also add a 100nF capacitor near the +Vcc and -Vcc pins of the ua741 to prevent the autoscillation
