Special thanks to Pajiba and Joanna Robinson for pointing me in the direction of this video. I'm fascinated by musicians who use live looping. This is the process where a musician--a vocalist or an instrumentalist--samples/records their own live performance and repeats it through a dedicated device (usually a stomp pad but sometimes a computer or other control device) to layer their performance upon itself. I believe this lovely performance of "Canon in D" by Pamelia Kurstin demonstrates it beautifully.
See, she records the initial sequence on her control panel (placed in the round antennae of the theremin) and then begins to perform over her own recording she made on the spot. It's a really cool bit of musical trickery that I'm surprised more musicians aren't taking advantage of yet.
Enter The Piano Guys. They have created an original piece of music called "Michael Meets Mozart" that couldn't exist without looping. Cellist Steven Sharp Nelson loops a combination of two five string electric cellos, one five string acoustic cello, and rhythmic phrases performed on the various cellos to create an ever-changing pattern of loops in this song. These are created with the red and black stomp pad on the floor. They are processed through the black and grey stomp pad to the right, which is connected directly to the digital bass drum that produces much of the drum texture in the recording. The so-called "ambient" sounds--the rosin on the strings, the tapping, the more percussive bowing--are recorded through the microphone that appears and disappears throughout the video.
At the same time, pianist Jon Schmidt is playing around with repeated phrases and rhythms with slight alterations on his electric grand piano. While some are attributing all of the drum sounds to his occasional clink of the piano lid, most of the percussion is performed by Steven Sharp Nelson. It is Jon Schmidt's contribution, however, that allows the song to transcend from showcase of modern technology to a work of art. The cello is mostly ambient and textural in the piece. It is the piano that produces the driving melody and dynamics.
Just watch and listen with a better understanding of how the piece comes together. It's more remarkable for the techniques I briefly touched on that they don't even mention on their video description. They deserve a lot more credit than "one piano, one cello."