Simms-Watts AP100 / PA100 preset

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

The Simms-Watts AP100 is a 100-watt British valve head: an ECC83 input stage, passive treble/bass stack, volume and a 'brilliant' control, then a long-tail inverter driving four fixed-bias EL34s. The PA100 variant uses the same power section with four paralleled mic preamps.

• Made in: UK
• Wattage: 100W
• Channels: 1
• Preamp tubes: 3× ECC83
• Power tubes: 4× EL34

Tags: british, vintage, el34, high-wattage, crunch.

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.