The Perfect Tone Bender! | Cunningham Amps MKII Professional Fuzz (OC76 Germanium)
NOS Mullard OC76 germanium transistors. An all-tube British-voiced 35-watt head. A 2x12" loaded with pre-rola Greenback recreations. And a tube-driven univibe along for the ride. All of it from the same builder in Auckland, New Zealand. Welcome back to Edge of Breakup.
In this episode, the Cunningham Amps MKII Professional Fuzz takes center stage — this time into my Wide Sky Guitars Tawa loaded with Curtis Novak Humbuckers and an Emerson Custom wiring kit and treble bleeds, running into a Cunningham Amps Custom 35 Head and 2x12" cabinet loaded with Scumback H75-PVC speakers. Guest starring the Effectrode Tube Vibe.
The Cunningham Amps MKII Professional Fuzz is Tim Cunningham's deeply faithful interpretation of the legendary Tone Bender Professional MKII — the circuit that defined the sound of late '60s British rock in the hands of Jimmy Page, Eric Clapton, and Jeff Beck. Three NOS Mullard OC76 metal can germanium transistors, hand-built one at a time in a heavy-duty wedge enclosure, individually voiced to their specific trio — no two ever alike. This particular example is the Sherwood Green aged and relic'd edition: Tim's weathered paintwork and hardware treatment giving it the look of a pedal that has lived a full professional life. Level, Attack, and three-way Gain Mode switch (Low, Med, High) cover the full spectrum from clean boost to full germanium saturation.
What makes this episode different from the first MKII video — and why it needed its own dedicated session — is the rig. The Wide Sky Guitars Tawa is a remarkably musical instrument: a semi-hollow build from Wide Sky's Todd Meehan, loaded here with Curtis Novak humbuckers and an Emerson Custom wiring kit and treble bleeds. Curtis Novak's humbuckers are wound with a meticulous attention to vintage specification and voicing that gives them a clarity and definition unusual in a humbucker — they retain note separation and harmonic complexity that pairs beautifully with a three-transistor germanium circuit. The treble bleeds keep the top-end detail alive as you roll back the guitar volume for dynamics, which in a fuzz rig is an essential practical tool.
And then there's the amp — which is the detail that makes this video genuinely special. This is an all-Cunningham chain: Tim's fuzz running into Tim's amp. The Cunningham Custom 35 Head is a hand-wired, all-tube 35-watt powerhouse featuring two independently voiced channels — Channel 1 running a tweed-style voicing from crystalline cleans to full "dimed on 12" overdrive, Channel 2 delivering British Plexi character for crunchy rhythm and singing leads. The channels can be run independently, in parallel, or cascaded — an extraordinary degree of tonal flexibility for a two-channel head. The cathode-biased output stage, fitted with EL34s as standard and swappable to 6L6 or KT66 without re-biasing, adds an organic, singing quality that is central to the amp's character. Tube-driven spring reverb is built in.
The 2x12" cabinet loads two Scumback H75-PVC speakers — Jim Seavall's faithful recreation of the pre-1971 G12H 25W Kraft paper voice coil "Greenback" T1217 003 Pulsonic cone, as heard in Marshall stacks and BluesBreaker combos of the pre-1968 British rock era. Woodier and more upper-mid-forward than the H75, with a good low end and less pronounced mid hump than the M75 — the speaker Scumback describes as the choice for players who want to sound like early Zeppelin. With a Cunningham MKII fuzz into them, it's an extraordinarily natural pairing.
This is Tim Cunningham's complete vision for what boutique guitar tone can be.
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🎸 Wide Sky Guitars Tawa | Curtis Novak Humbuckers | Emerson Custom Wiring Kit & Treble Bleeds
🎛️ Cunningham Amps MKII Professional Fuzz | Sherwood Green Aged Relic | NOS Mullard OC76 Ge Transistors
🎛️ Effectrode Tube Vibe
🔊 Cunningham Amps Custom 35 Head | 2x12" Cabinet | Scumback H75-PVCs
