Using it for Guitar Amp ("Brown-Sound") and for controlling a transformer for Lichtenberg wood burninga variable AC input to a transformer input DC bridge rectifier to produce a variable outputThis variable transformer is the perfect speed controller. The speed is infinitely variable, and because a transformer doesn't chop up the AC waveform like electronic speed controllers do, there's no noise, humming, etc.In order to purchase the right variable transformer, it is critical that you know the amp usage by your electronic device. It is always best to be conservative otherwise you risk destroying the variac and it can be very dangerous. For example, if your device requires 5 amp, buy the variac with up to 10 amp. A rating of 500VA means that at 100volt, the unit can sustain at maximum 5amp.Max. 500VA,Input Voltage: AC 110V/60Hz ,Output Voltage: AC 0-130V/60Hz