The "Pedal" keyboard is integral to theatre organ as it's used to play the bass line. If you want to hear the Pedal in action, you'll need to listen on a decent sound system or pair of headphones (most phones, tablets, and earbuds won't reproduce those low frequencies). If you want to see the Pedal keyboard in action in the video, jump to the camera shots at 00:56 , 08:17, 13:10, or 21:29 (just to highlight a few). On two of those examples, you'll also hear that Ken is using the Pedal to play the tap cymbal in conjunction with the bass.