Introduced in the late 1960s, the wah-wah is a specialized foot pedal, similar in shape and appearance to a volume pedal. By rocking the pedal up and down whilst playing, the mid to upper frequencies are fluctuated creating a human-like 'talking' effect – as its name implies. The wah-wah pedal is particularly associated with 70s and 80s funk – listen to Isaac Hayes' theme-song from Shaft.