Yamaha RBX6JM

The Yamaha RBX6JM was the first John Myung-signature six-stringed electric bass.

A bolt-on bass with alder body and flame-maple top available in either "Ruby Red" or "Turquoise Blue" with a maple neck, ebony fretboard, gold hardware, 35" scale, and "Infinity" dot inlay on the fretboard, various Red and Blue "RBX6JM" models were his main studio and live instruments along with his TRB6 six-string fretless from 1997-1998's Touring Into Infinity, 1998's Once In A LIVEtime double-disc live CD and 5 Years In A LIVEtime video, 1999's Metropolis Pt. 2: Scenes from a Memory, following tour and 2001's Metropolis 2000: Scenes From New York DVD and Live Scenes From New York three CD live set.

In 2002 John Myung and Yamaha unveiled the RBX-JM2, an updated version of his signature bass that echoed the redesign of their entire RBX-series of basses. Changes included a modified body shape with more "modern" lines and carvings, finishes in either "Inca Silver" or "Plum Purple" in flat as opposed to glossy paint, slightly tighter string-spacing, a maple neck/rosewood fretboard with "Yin-Yang" inlay at the 12th fret, 34" scale as opposed to the 35" scale that the RBX6JM had, and most importantly a single Music Man-style Seymour Duncan SMB6A humbucking pickup, by all accounts an influence from his usage of a Music Man Stingray to record a good portion of Dream Theater's Six Degrees of Inner Turbulence.

In July 2007 Myung officially endorsed Music Man and their new six-string version of the Music Man Bongo bass guitar.