Sonus Series - Sonus BG4 Billy Gould Signature Bass

Designed in collaboration with Bill Gould, bassist for the band FAITH NO MORE, this highly anticipated bass features a tulip wood body, ZON’s proprietary bolt-on, composite neck and two custom-wound Bartolini pickups.

One of the unique features of this signature bass is the single master volume control on the face of the instrument and the location of the bass and treble controls for the active circuit on the rear cover plate. However, the most distinguishing feature of the BG4 is the on-board, touch-sensitive, distortion circuit, designed for this bass by Roy Zichri of Greenhouse Effects. When engaged, this circuit gives a grit and edge to the tone of the bass providing Bill’s distinctive sound. The BG4 is the first bass on the market to incorporate this feature.

Completely handmade by ZON in their Redwood City, California, US facility, the BG4 is finished in satin black and is appointed with black hardware and a Hipshot D-tuner. A limited number of these basses will be produced with the first 25 personally signed by Billy Gould.

For a full-size image of the complete bass, please CLICK HERE. Image will open in a new window.

Street price for the BG4 is $3599.00, including gig bag.


  • Material: Two-piece select tulip wood
  • Finish: Flat Satin
  • Color: Black


  • Type: Composite, bolt-on design
  • Scale length: 34"
  • Finish: Flat satin
  • Truss rod: Dual action
  • Fingerboard: Phenowood
  • Radius: 12"
  • Nut: Graphite
  • Frets/size: 24/medium
  • Width at nut: 1.532"
  • Width at 24th fret: 2.437"


  • Type: Proprietary custom-designed preamp by Roy Zichri of Greenhouse Effects with touch-sensitive on-board distortion circuit.
  • Functions: Single master volume and distortion switch on deck with all other preamp controls accessible through rear cover plate.
  • Power requirements: Single 9-volt battery
  • Life expectancy: 300 hours of continuous use.


  • Make: Proprietary BG design made exclusively for Zon by Bartolini.
  • Type: Neck pickup is a wide-aperture, passive, dual coil design in a soapbar style shell. Bridge pickup is a narrow-aperture, passive, linear single coil design in a JB style shell.


  • Bridge: ZON machined brass.
  • String spacing: 19mm (string-to-string)
  • Tuners: Gotoch GB-7 with Hipshot Xtender
  • Finish: Black


  • Left-handed


  • Gig bag included


Watch the above video from NAMM 2015 to see Billy do a quick demo of the custom circuit.