Pete Cornish Deluxe GC-1

The Pete Cornish Deluxe GC-1 is a three-stage overdrive pedal with a three-band active EQ, released in 2021 to mark Pete Cornish's 45th year designing and building professional stage equipment¹. Pete Cornish describes it as a completely new, unique three-stage design featuring both hard and soft clipping stages, with automatic switching between them as the gain increases¹. Delicious Audio profiled it at launch as a high gain crunch drive, noting that it can deliver soft and transparent sustain at low gain levels, '70s Marshall-style overdrive at medium levels, and an intense overdrive at maximum gain².

The pedal is analog throughout, built around Pete Cornish's well established Class A input buffer (the LD-1) and a radio frequency suppressor, followed by the gain stages and the active EQ¹. Like other Pete Cornish pedals, each unit is hand built, wired and tested by Pete, Lynda and Mingus Cornish³⁴.

Three-stage overdrive with hard and soft clipping

The core of the Deluxe GC-1 is its gain structure. Pete Cornish describes the circuit as a three-stage design in which the pedal automatically moves between hard and soft clipping stages as you turn the gain up¹. The maker maps the pedal's gain range onto four territories:

• Minimum gain (+20dB): the area of Soft Sustain, as found on the SS-2 and SS-3
• Low gain: Blues Crunch
• Increased gain: a higher level of overdrive
• Maximum gain: High Energy Sustain³

On the sound, Pete Cornish says the pedal offers "A wonderfully Smooth and Transparent Blues Crunch" at low gain settings, with what the maker calls amazing Bottom End Retention, Refined and Warm without getting muddy¹. The Battery Free GC-1, a related version, is also described by the maker as having an "amazing clean up" using the guitar volume control³.

An independent technical analysis by Aion FX tells a more specific circuit story. Aion FX found the GC-1 uses the same PCB as the Cornish CC-1 with several component value swaps, and that its clipping is the same as the CC-1, which Pete Cornish describes as having two soft clipping stages. In Aion FX's words⁵⁶:

So the maker's description of hard and soft clipping stages with automatic switching, and Aion FX's finding of two soft clipping stages shared with the CC-1, are two published accounts of the same circuit, and they disagree on what the clipping arrangement actually is. Both are given here as stated. Aion FX also notes the build style: a vintage-style etched single-sided PCB with epoxy-potted component blocks⁵.

The controls: gain from +20dB to +56dB

The Gain control sets the overall boost across a wide range. With Gain at 0% and Volume at 100%, the overall boost is +20dB (10X); with Gain at 100% and Volume at 100%, it is +56dB (640X)⁷. That span is what lets the pedal cover everything from low-gain Soft Sustain to High Energy Sustain without touching another knob.

The active EQ sits after the clipping stages, a layout Pete Cornish also uses on the CC-1, where the maker says the EQ frequencies were specifically tailored to suit guitars⁸⁹.

Power and connections

The Deluxe GC-1 runs on a 9V DC adapter that Pete Cornish specifies should be noise free, fully stabilised and capable of supplying 20mA. The coax connector is 5.5/2.1mm with the center pin negative (-VE), the same convention as most standard pedal power supplies¹.

It also runs on a 9V battery, preferred type MN1604, replaced through a removable drawer. The battery switches on when you insert a plug into the IN/PWR ON jack, so the pedal draws no power with the input unplugged¹.

The enclosure is a rugged die-cast box measuring 171 x 121 x 55 mm (6.75 x 4.75 x 2.2 inches) with lined control knobs, a heavy duty custom made all-metal footswitch and a daylight visible LED¹¹⁰. That footprint matches the Deluxe SS-2 and Deluxe P-2 in the same series¹¹¹.

Built on the SS-2, SS-3, G-2 and P-2 circuits

Pete Cornish himself situates the GC-1 within the family lineage: at minimum gain the pedal is in the area of Soft Sustain as found on the SS-2 and SS-3, while the mid gain settings pass through the gain structures of the G-2 and P-2¹. Those four pedals form the reference points for what the GC-1 does at different gain settings.

Independent tracing work by Aion FX and Kit Rae has shown how closely those reference circuits are related to each other. The P-2 was created as an updated version of the P-1, and the G-2 uses the same PCB as the P-2, with 16 components changed to reduce the gain and change the EQ¹². Kit Rae's account agrees:

Aion FX found the same pattern in the GC-1 itself: identical to the CC-1 other than changes in component values⁶. The CC-1, in turn, is described by Aion FX as a fully original Pete Cornish design, not based on anything else, designed primarily with op-amps⁶. So while the GC-1's gain territories are voiced to recall the SS-2, SS-3, G-2 and P-2, the circuit underneath is, on the independent account, Cornish's own op-amp design shared with the CC-1.

For players comparing the line, the practical differences are the gain range and the clipping arrangement: the CC-1 pairs two fixed low-gain soft clipping stages with a variable gain preamp of up to +22dB and a +34dB overall boost at full settings⁶⁸, while the GC-1 extends the overall boost to +56dB and, per the maker, adds automatic switching between hard and soft clipping as gain increases⁸⁹¹⁴.

Warranty

Pete Cornish pedals carry a twelve-month warranty from date of purchase. Should a fault occur in that period, the pedal is returned post paid for repair of any original manufacturing fault. The warranty is voided if the guarantee labels are damaged or removed¹.

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