Sunn 1000S preset

Verified · 91/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The Sunn 1000S (1969) is a high-powered bass/instrument head with Normal and Bright inputs, volume, bass, treble, contour and a midrange boost switch, plus 12AU7 spring reverb and photocell tremolo with transistor oscillator and reverb recovery. A 6AN8 driver/inverter feeds four 6550s, with dual GZ34 rectifiers at about 525 V.

• Made in: USA
• Wattage: 120W
• Channels: 1
• Preamp tubes: 1× 12AX7, 1× 12AU7, 1× 6AN8
• Power tubes: 4× 6550

Tags: american, vintage, 6550, bass, reverb, tremolo, high-wattage.

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.