Guild 66-J - Instrument preset

Verified · 89/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

A Guild combo with two instrument inputs and a mic/accessory input, each group with its own volume, sharing bass and treble. It has 12AX7 tremolo with speed, strength and footswitch, a 12AX7 inverter, and two 6V6GTs with a 5Y3GT rectifier. It is a small, warm American tube amp from Guild's early amp line.

• Made in: USA
• Channels: 2
• Preamp tubes: 3× 12AX7
• Power tubes: 2× 6V6GT

Tags: american, vintage, 6v6, tremolo, two-channel.

Schematic-derived preset files for 16 Fractal and Line 6 modelers: Axe-Fx II/XL/XL+, Axe-Fx III, FM3, FM9, and the full Helix family (Floor, LT, Rack, HX Stomp, HX Stomp XL, Native).

Gridleak extracts amp parameters from original circuit schematics using AI vision — component values, gain staging, tone stack topology, tube types — then generates native preset files for every supported modeler. Every extraction is scored 0–100 and the score is published.