Originally Published in The Tentacle in 2002
Corporal Callosa are specifically designed instruments using piano strings (under high tension), which have a high upper-harmonic content. They are essentially custom-size replications of the conventional piano hearth, but contain no keys, resembling a hammered dulcimer. The strings are prepared (a process using mechanical stops placed at strategic harmonic nodes of the string and developed by John Cage in the 1930s) and played with mallets, screwdrivers, bows, and picks. This results in darker sounding sub bass tones. While bowing very rich harmonics are produced, different than the sound of most string instruments with strings at pow tension. The stop material and harmonic placement determines the timbral quality of each sound. These instruments are acoustic in nature, but are amplified by the use of pickups and processed electronically sounding through stereo Leslie speakers. They sound similar to the sounds from the gong chime culture of Southeast Asia, or more specifically, Gamelan music. By adding effects, they can generate a wide variety of sound to the point of a heavily processed rock guitar.
My prototype was built in 1995 and named the Lilith, because of its demonic shrillness from the effects I was using at the time. It is still being used, but I don’t take it out as often. I then changed its name to Corpus Callosum, after the region of the brain uniting the cerebral hemispheres comprised of the commissural fibers. I think of this instrument as a hybrid, bridging two schools of thought: acoustic and electronic.
I built the corpus as an addition to my keyboard rig (including Hammond, Rhodes, and various vintage synthesizers), rounding out the sound, and to be played on stage or in a club setting. Six instruments exist today, with one being build for drummer Matt Chamberlain.. In 1997, after playing in live stage settings, the stock Leslie speaker sound was no longer adequate because of volume vs. feedback issues resulting in distorted sound from trying to turn up with not enough headroom. I then modified the Leslie amp into a stereo Leslie p.a. I employ a bi-amp with separate sends to each individual horn and woofer with a total of 2600 watts, plenty for any house without a reinforcement system, or for use as a monitor. I also gutted the two-speed synchronous motors controlling the vibrato/tremolo effect of the Leslie and installed variable-speed, independently controlled motors for a more diverse vibrato/tremolo, which in turn creates ratio metric rhythms from the oscillations of the speakers, and further enhances the overall timbre of the instruments.
