Guitar Effects: Wah Wah
Wah-wah pedals filter the frequencies of the incoming guitar signal to give it a distictive, human-like sound when rocked back and forth.
Wah-wah pedals are used by many famous guitarists in their riffs and solos. Some guitarists use wah-wah pedals in one position to create a filtered tone, while others play them the conventional way of rocking the toe of the pedal up and down. This creates a sound similar to a person saying "wah" hence the name.
Auto Wah effects mimic wah-wah pedals, but do not have the foot rocker found on normal wah-wah pedals. The incoming guitar signal triggers the effect to create wah type sounds automatically.