Classical, Jazz, and Experimental Guitar:
Guitar was Joshua's first musical instrument; he began with an electric guitar at age ten. During high school he studied classical and jazz guitar, played in the LaGuardia High School Junior Jazz Band and in Manhattan School of Music's Summer Jazz Workshop, lead by Justin DiCioccio. He also twice attended the National Guitar Summer Workshop.

His own electric jazz quintet from those years featured Abraham Burton (sax), Tobias Raph (drums), Frank Cotto (bass), and Eric Mcpherson (percussion). Recently, Joshua seldom plays guitar, preferring other instruments instead. It was thought that no known recordings of his electric guitar playing survive, but see below.

Here are some sound clips of him playing classical guitar when he was in high school.

Leo Brouwer: Etude No.3 mp3 0:28
Leo Brouwer: Etude No.6 mp3 0:50

Many thanks to guitar wizard minimalist sound-art improvisor Alan Licht, who recovered a recording of Joshua performing an electric guitar improvisation when 16 years old at the National Guitar Summer Workshop.

Distorted electric guitar improvisation mp3 5:42
Special techniques (swelling, tapping, etc.) finale of the improvisation mp3 3:30