B-52 AT-100 - Gain 1 preset

Verified · 86/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The AT-100 is B-52's 100-watt all-tube head. A Clean channel with its own volume and bright switch sits beside a relay-switched overdrive side with two gain modes, each with its own gain and level, plus a contour control; treble, middle and bass are shared. A 12AT7 drives spring reverb with level and mute, there is an effects loop with send and return levels, and a 12AX7 inverter feeds four 5881s with presence, on a 5AR4 rectifier.

• Wattage: 100W
• Channels: 3
• Preamp tubes: 6× 12AX7, 1× 12AT7
• Power tubes: 4× 5881

Tags: high-wattage, modern, multi-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.