Onyx Plus

633 Engineering’s Onyx+ is one of the finest amplifiers that I’ve had the pleasure of playing through
— Sound on Sound magazine review - October 2015

The Onyx Plus takes the specification of the Ruby and adds Tremolo and a solid state rectifier to produce a tighter response and bump up the maximum output power to 45 watts. The relatively simple feature set of the Onyx + makes getting great sounds a straightforward process. This amp excels at clean sounds breaking up smoothly when pushed.

  • 2 x 6L6
  • 3 x 12AX7
  • Volume, Tone
  • Tremolo with Speed and Depth Controls
  • Foot switch-able More boost and Tremolo on/off
  • Reverb level control and 4 way interaction with More
  • 3 position Voice switch
  • 5 position Variable Headroom switch
  • Cab Simulator output for DI into PA and recording
  • 515mm x 211mm x 214mm, 15kg
  • All hand built in the UK

Unlike many other designs where the tremolo modulates both the dry and reverb signals, the Tremolo in the Onyx Plus operates around the first valve stage, before the reverb.  This means the guitar signal is modulated by the tremolo first and then the reverb is applied to this signal allowing some very sophisticated tones to be produced. 

Check out the full Sound on Sound magazine review here....


Check out some audio clips of the Onyx+

Onyx + with Compact 1x12 cab