Multitimbral Cello
The ‘Multitimbral Cello’ hails from two of my biggest academic affinities: altering how we interact with music, and exploring how we understand how we interact with music. Its lovably jargon-filled name attempts to capture the portable device’s founding principle: to expand the cello’s timbral palette (the texture of sounds it can create) towards those used by synthesizers and multi-effects guitar pedals via the manipulation of the instrument’s physical body alone.
In one sense, the project was born out of pragmatism. In a year where our lives moved online, I felt compelled to create something tangible; physical. And as an overzealous first-year assuming perhaps a *few* too many commitments, I knew that maximizing my Shift experience would necessitate blending it with others — allowing my circuit design skills from Solar Car, audio programming techniques from my research, and musicological insights from cello lessons to inform my work. An interdisciplinary offering indeed.
At the same time, the idea’s growth stemmed from the sort of stubbornly starry-eyed idealism characteristic of a naïve freshman inaugurated into a community of inspirants. I recall inundating my physics professor during office hours (love you, Brad!) with an assortment of electroacoustics-related questions, attempting to probe the future and discover the degree to which certain facets of the endeavor were even possible.
Thrilling, terrifying, and thrillingly terrifying: just how the first month of college should be.
Although the ocean that is embedded systems design deepens quite quickly (and so I won’t dive in here), there are in essence only three constituents whose constant interplay controls the creation. The first involves input from the instrument — a piezo pickup attached to the cello senses the pressure vibrations it makes while being played and converts them into an electrical signal. Secondly, two surface transducers convert electrical signals back into vibrations — which the cello will happily conduct to produce sound on top of the music it’s currently making.
And finally, in between these two processes lies the processing of the signal. This is where a tiny computer — a microcontroller — within the surrounding circuitry can be programmed to transform the incoming signal from the instrument into something new before it heads out back toward it. The dials pictured above give the performer a way to customize the sorts of transformations which will be applied to the signal and how strong each effect will be.
Examples of such transformations include effects often used with guitars/synthesizers and in sound production — reverb, delay, chorus, and a few others. There are some manipulations specific to the cello itself, too: my personal favorite for experimentation is the 3-part harmonizer, while my favorite to develop was a mechanism which ‘induced’ a wolf tone¹ for every note on the cello.
I envision the device’s primary use case to be a subtle one. Just add a hint of reverb here and a soft octave doubling to accentuate secondary harmonics there, and suddenly, Bach on the beach (an environment notorious for dry sound) sounds somewhat richer— though the effects applied are only slightly audible.
Sometimes, though, you just need to jump in, turn everything on & everything up, and hope the result breaks neither the instrument nor your ears²:
Thrilling, terrifying, and thrillingly terrifying — a microcosm of the beautifully reckless idealism which Shift teaches us to embrace.
About Jake
Jake is a first-year student at Michigan studying Computer Engineering and Cognitive Science.
When not doing math-y, music-y, or mind-y stuff, he enjoys playing sports and traveling.
Say hello at jakehume@umich.edu!
- When played near their resonant frequency, string instruments like the cello will often produce a peculiar, warbling sound known as a wolf tone.
- Both instances may or may not have occurred during the early days of testing…
