Diagram of normal sinus rhythm as seen on ECG. In atrial fibrillation the P waves, which represent depolarization of the top of the heart, are absent.
The wah-wah pedal is based on a simple concept but its effect is far more dramatic. Using a powerful filter to sweep through a broad frequency spectrum, the wah pedal boosts and exaggerates specific tones. Creating sounds that range from thick, flubbery bass to scratchy, stinging treble.
In some cases, volume and expression effects pedals are one and the same. Multiple outputs allow you to control volume and effects separatelyâor, if you feel so inclined, both at once. An expression pedal is designed to accompany a multi-effects unit, amplifier or synthesizer that supports it.In a setup like this, the pedal gives you precise control over such things as the frequency of wah effects or the rate and time of modulation and delay effects.igh-quality pedals with metal construction are the norm, so you won't have to look far to find a pedal that can take some punishment. Your volume and expression effects pedals put the most important characteristics of your sound directly into your control.