Sundown Rebel 50 / SDR-100H preset

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

The Sundown Rebel 50/100 Lead (SDR100H) is a 1985 American single-channel tube head. Two inputs feed cascaded 12AX7A stages with a Gain control and a Pull Boost (also on a footswitch jack), a preamp effects loop, then Treble, Bass and Mids and a Master, followed by a power-amp effects loop. A 12AX7A long-tail inverter with Presence and negative feedback drives 6L6GCs in fixed bias — two on the 50, four on the 100 — with an RMS power-reduction control and a pull-switch Governor. Silicon bridge rectifier, standby, 4/8-ohm outputs.

Tags: american, 6l6, crunch, mid-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.