Electro-Harmonix Doctor Q effects pedal

The Electro-Harmonix Doctor Q is an "envelope follower" effects pedal that dynamically alters a guitar or bass signal in response to playing intensity. Designed to produce an automatic, "wah"-like effect without the need for a dedicated control pedal (such as a wah pedal), it reacts to the musician's picking attack—opening or closing a frequency filter based on the strength of the signal. The Doctor Q retains a simple yet expressive design, capable of producing a wide range of filter effects—from percussive and vocal-like tones to highly distinctive, unique sounds. Made in the USA