Selmer Thunderbird 100 preset

verified · 80/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The Thunderbird 100 is a valve head from Selmer London’s Thunderbird series. An ECC83 input stage feeds a switched Selectortone-style tone network and volume, then more ECC83 gain stages. A 6BR8 drives the spring reverb through a transformer, with triode recovery and level, and an ECC83 oscillator runs a light-dependent-resistor tremolo. An ECC83 long-tail inverter with presence drives four fixed-bias EL34s, with BY128 silicon rectifiers.

• Made in: UK
• Wattage: 100W
• Channels: 1
• Preamp tubes: 4× ECC83, 1× 6BR8
• Power tubes: 4× EL34

Tags: british, vintage, high-wattage.

Schematic-derived preset files for the Neural DSP Quad Cortex and 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.