"A wah-wah is important as well. I love it; it makes the guitar scream"

This quote by Robin Trower is referring to the use of a wah-wah pedal in guitar playing. A wah-wah pedal is an impacts pedal that alters the tone of the guitar by altering the frequency of the sound. It is typically utilized to develop a "screaming" sound, which is what Trower is referring to in his quote. He expresses his love for the noise of the wah-wah pedal, as it can include a special and powerful component to a guitar solo. The wah-wah pedal has actually been utilized by many popular guitar players, including Jimi Hendrix, Eric Clapton, and Stevie Ray Vaughan. It is a necessary tool for any guitar player looking to add an unique and powerful sound to their playing. Trower's quote is a testament to the significance of the wah-wah pedal in guitar playing, and his love for the noise it can develop.