Guild Thunder 1 T1-12 preset

Verified · 88/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The Thunder 1 T1-12 is a mid-1960s Guild combo, from a May 1966 drawing, with Normal and High-Gain inputs into one channel with bass, treble and volume controls and a bright switch. Half of a 12AX7 runs a tremolo with speed and intensity and an on/off switch; there is no reverb. Two 6GW8s finish the circuit: their triode halves form the gain stage and phase inverter and their EL84-type pentode halves run in push-pull, on a 6CA4 rectifier.

• Made in: USA
• Channels: 1
• Preamp tubes: 2× 12AX7
• Power tubes: 2× 6GW8

Tags: american, vintage, tremolo, low-wattage, breakup.

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.