The Mechanical Monk (above) is a two stringed, motorized instrument played with two steel rods as slides. It sounds like a cross between Tibetan monks and an alien spaceship (as opposed to the government spaceships-- they sound completely different).
The Chariot in motion: the chariot consists of two motorized bicycle wheels with shakers attached. The speed of each wheel can be adjusted and the shakers can be moved to set up different rhythms.
The m'birangi: thirty-two tunable metal tines suspended over a two foot long electromagnetic pickup. The tines are plucked with the fingers. The eight strings are vibrated by magnets spun by a motor, for an ethereal, haunting sound.
A movable-fretted, microtonal electric guitar. It has a unique pickup which uses electromagnetic principles, but not in the usual way.
Two movable-fretted, microtonal acoustic guitars, modified from standard acoustics (one mini).
The cellotar is one of the precursors to the alumitar (left).
The alumitar has ten strings and is played with a bow or plucked.
The cellotar has six strings.
Other instruments in this series include the viotar (four strings); the invisitar (five strings, made of clear acrylic); and the ubertar (see pic below).
The alumitar: ten strings, played with a bow, has electromagnetic pickups and the full range of a piano.
The electric saron: tuned steel rods struck by mallets, suspended over a huge electromagnetic pickup (possibly the world's largest humbucker). There is a switch to change the coil configuration to either parallel or series, and a high-pass filter knob to cut the "thump". Rods have been cut for standard tuning, 9 tone equal temperament (tet), 10 tet, 13 tet, 14 tet and 15 tet.
An earlier version of the electric saron.
The oscillator array: a collection of various oscillators with pitch and volume controls, with stereo or mono output.
The original microtonal guitar. Built in 1992, this was Rubenstein's first creation. Originally it had movable, nylon frets, but is now fretless.
On the left is a solid-body electric setar, with humbucking pickup. To the right is a traditional, acoustic Persian setar.
The ubertar (detail).
Paul playing the ubertar. The ubertar has eight melodic strings and two automatic drone strings.
A group of microtonal guitars (right). These are tuned, from left to right: 10 tone equal temperament (tet), 12 tet, 13 tet, 14 tet, and 15 tet.