Suspended Bowls + Motor-Array Instrument

A motor-array instrument crafted of bowls, bells, balls, beads and (b)clothespins. A vibration motor is attached to each suspended bowl and controlled from an arduino-based interface.

GitHub Repository

Expressive Control

The control for this instrument is based off the interface originally built for my bell controller, though the modes and timings have been customized to better fit the acoustic material.

  • Continuous vs. pulsing
  • High-resolution pressure/frequency control

The structure of the program is based on a single motorcontrol() function. Each motor uses the same function with slightly different parameters. All logic is self-contained in the Arduino. You can view the code on github.


The following materials were used in addition to the motors and control interface.

  • Resonators: plastic bowls and cups
  • Fillings: beads, ping pong balls, bells, bingo chips, clothespins
  • Stands: monofilament, wood, threaded metal rods, hex nuts, rubber bumpers, sticky tack, felt
  • Performance aids: magnetic wand, overhead projection

Special thanks to Liam Mooney for advising on the construction of the bowl stands.


"Performing" the instrument involves manipulating the fillings, adding or removing "mutes" (cups), and altering motor states via the control interface. A magnetic wand aids in quickly removing materials from the bowls, and an overhead projection is recommended to increase visibility.


The Wire

"Stephanie Cheng Smith/Liam Mooney/Sarah Hennies's Everything Else", The Wire, September 2020, Issue 439, p.85

Performing b-z-bowls on Indexical's livestream on July 11, 2020
b-z-bowls prototype preview (March 2019)


Related Events

09-01-2020  -  Press: b-z-bowls in The Wire

07-11-2020  -  Indexical Livestream: Stephanie Cheng Smith + Liam Mooney + Sarah Hennies , 5pm Pacific , twitch.tv/anindexofmusic

02-24-2020  -  Research + Practice Visiting Artist: Sonic Instrument Building Lecture , CalArts

12-07-2019  -  Anderson and Wambsgans, Putman and Naim, Smith , 8pm , Coaxial

04-18-2019  -  Visiting Artist Lecture: Composition-ESP Forum at CalArts , 4:15pm , CalArts B305

03-27-2019  -  PIE: Wired Wednesday , 8pm , Live Arts LA