The Electro-Harmonix Nano Dr. Q Envelope Funk Effects Pedal is everything you love about the regular Dr. Q in an even more compact, die-cast package. This compact battery operated envelope device features a Range knob, with an LED status indicator. The effect responds to how hard you hit the string and where the guitar volume control is set. If you hear plops and clicks back it off. When it's set just right you will be able, with some practice, to get different effects depending on whether you play loud or soft. The bass switch lets low sounds through when it is down, and is especially useful when playing bass guitar or bottom string notes on lead guitar.