This is a tube-driven envelope-controlled filter that offers the user an extensive array of automatic wah and swept filter effects in a compact pedal format. With its somewhat relaxed tracking and warm tube tone, the sounds that come out of the Funky Box are often unpredictable and never boring! The second offering in the Guyatone Flip Series of tube-powered floor-effects, the FB-X Funky Box is the final word in filters! The FB-X is a tube driven envelope-controlled filter that offers the user an extensive array of automatic wah and swept filter effects in a compact pedal format. The FB-X's Threshold (determines strength of effect) and Decay (determines the speed of the effect) controls allow the user to preset the unit's filter sweep, while the Level control adjusts the unit's volume and can also be used to overdrive the input of an amplifier. Switchable wah modes allow the Funky Box to operate in multiple frequency bands, making the FB-X perfect for use with any instrument including Guitar, Bass and Keyboards. Effect LED indicator and electronic silent switching make the FB-X ideal for live or studio performance Be warned: The FB-X is not for the faint of heart. With its somewhat relaxed tracking and warm tube tone, the sounds that come out of the Funky Box are often unpredictable and never boring. It's a squawking, burping, bleeping, farting filter fiasco that finally answers the question: Who's got the funk? The answer, of course: Guyatone.