The TubeMeister 18 features independent GAIN and MASTER controls for the CLEAN and LEAD channels. Think of GAIN and MASTER as the yin and yang of sound-shaping rather than volume controls. They let you voice the TubeMeister 18’s two channels. To set the basic volume level for the stage, rehearsal room, or living room, use the POWER SOAK on the back of the amp. The best way to discover the amp’s sonic possibilities is to experiment: Set the POWER SOAK to five watt mode and all knobs to the 12 o’clock position. Then adjust GAIN/MASTER settings at will to get a taste of the very different flavors of preamp and power tube distortion. To avoid very loud and unwelcome surprises, make a habit of backing the VOLUME knob of the guitar connected to the TubeMeister all the way down before switching on the amp.