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.
During your pedal stroke, you use the muscles in your legs and hips. More specifically, your gluteus muscles work in the first part of your downstroke as you power down the pedal, and your quadriceps and calves finish the downstroke. Your hamstrings work in the recovery phase, as the pedal returns to the top.