In addition to guitars, basses, 'uds, and banjo (Gibson, Duesenberg, Martin, Ramirez, Wildwood and Ihsan Dinçer Dalkiliç, for those who want to know), I have designed some custom, one-off instruments built by Dan Strack, a talented and generous luthier in Chicago.

7-string redwood archtop guitar, flamed maple back and sides (2008)

I commissioned this mostly out of frustration with transposing the lower notes (C through D#) when playing Bach's cello suites on the electric guitar. The low range of the 7th string (tunes to C) adds a depth to the already dark timbre from the redwood top. I use the Brazilian 7-string tuning CEADGBE.

As Dan and I worked out the details, we came up with a general idea to create an electric guitar that was up to the standards that I had for playing art music—range of timbral options, the "woodiness" of a jazz archtop, and the wider fingerboard of a classical guitar. Dan delivered all this in spades, complete with beautiful woods, a viol-inspired inlay on the back, Jason Lollar P-90 and humbucker pickups, and one rear-facing tuning gear to keep symmetry of a 6-string on a 7-string.

I debuted the guitar with the Los Angeles Electric 8, adding a rich lower-register to our arrangements of Bach and Messiaen. At present, I am developing a solo repertoire for the instrument and using it in BERIO, jazz combo (with baritone saxophone and drum set) adaptations of and improvisations around Luciano Berio's Duetti per Due Violini.

Stay tuned for recordings of this beauty.

Solid-body electric sympathetic 'ud (2005)

In an attempt to mash together my Gibson SG, 'ud and viola d'amore, I worked with Dan to create this 24-string mahogany electric sympathetic 'ud. Much of this design was an attempt to improve on the 1/2 fretless sympathetic guitar (below). First, we lengthened the sympathetic strings so that they would have more resonance. This required running them through the neck, under the fingerboard as with the Baroque viola d'amore. Due to the number of strings (12 sympathetic and 12 played) and no room for a truss rod, Dan reinforced the neck with baltic birch plywood (used by Framus guitars) and carbon fiber reinforcement strips. A jazz-style floating pickup is attached to the fingerboard and a blade pickup runs under the sympathetics giving each some separation through a switched stereo output.

The instrument is well suited for Arab music. I debuted the instrument with A. J. Racy's ensemble. During the concert, we highlighted the instrument in a solo during "Longa Shahnaz." It also came in handy while accompanying dancers (I could hold my own against the loud percussion and synthesizer). I also used the instrument more freely for the soundtrack to J.R. Hughto's The Thin Time, capitalizing on the resonance of the octave-doubled lower courses and sympathetic strings—check out the music on the trailer.

1/2 fretless sympathetic guitar (1999)

This was my attempt at combining elements that I liked from three different instruments—the frets of a guitar that ease making chords, the fretless fingerboard of a Near Eastern 'ud that is expressive melodically (and allows for precise microtones) and the sympathetic strings of a sarode or sitar that produce a deep resonance, not unlike a sustain pedal on a piano (the placement is somewhat inspired by John McLaughlin's sympathetic strings on the acoustic guitar he used for his Shakti project). Dan modified an old Ibanez Roadstar guitar that I had been hacking at with modifications for years.

After some experimentation and a few shows (both free impov, non-idiomatic and two compositions I wrote for it), I realized that I had really created two instruments on one body: one low and fretted and one high and fretless. I settled on the following tuning: DGCDGC. Thus, the fretted lower notes have similar fingerings as the fretless strings, separated by an octave. The eight sympathetic strings running diagonal can be tuned to whatever notes need to be augmented (as with Indian instruments). The output is stereo so that I can run the sympathetic strings to a second amplifier and have the option of running effects on either the played or sympathetic strings.

I use this on several tracks on my solo album, Ce qu'a vu le Bordel d'Sud (2002).