The Maxon RTD800 Features independent Overdrive and Distortion circuits combined with a dual triode tube to offer a massive array of saturated tones, from traditional tube overdrive through full-on gated metal distortion. No other tube overdrive pedal offers this degree of versatility in a single package. Every aspect of the RTD800 has been re-thought and redesigned to provide a lifetime of trouble-free performance. As soon as power is applied to the pedal, an In-Rush Current Control circuit begins heating the tube at a very low voltage (much like a tube amp standby switch) to dramatically extend tube life. When the pedal is engaged, a charge pump circuit bumps incoming voltage to feed the tube with 12.6 VDC.