Ampeg SBT - Channel 1 preset

Verified · 84/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The Ampeg SBT is a solid-state bass amp drawn in 1969, sharing its power amp with the SST. Both channels have bright and normal inputs, Ultra Lo and Ultra Hi switches, bass, treble and volume; channel 1 adds a Bass Cut Off switch and a midrange control with a three-position mid-range switch built around a toroidal inductor. A summing amp feeds external amp jacks and a quasi-complementary transistor power amp driving two 8-ohm speakers.

Tags: american, bass, solid-state, two-channel, vintage.

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.