Model H - 4 Knob

Model 4H Overdrive/Distortion The new 4 knob Model H expands on the Standard Model H by slightly reducing the distortion and compression and adding a treble control. These adjustments are made only to the 4 knob version since the 3 knob version is much loved as is, and will continue to be produced. The new Treble control starts a little darker than the standard H and allows ample treble/upper mid adjustment. The Tone and Treble controls effect different parts of the circuit and combine to let you get the exact impact and definition you need for your rig. Voltage range is 8~12.

Pete Thorn (both H and DRD on first song)

Mike Hermans (Pop into the Chemist - 3 and 4 knob comparison near the end)