Ampeg B2RE (preamp board) - Main preset

Close · 78/100 confidence. Most values readable. Minor gaps filled by inference from similar circuits.

The B2RE preamp board documents the signal-processing section of Ampeg's solid-state bass head. The Main channel preamp provides Ampeg's characteristic bass tone shaping including the five-band graphic EQ and drive control. A key reference for technicians diagnosing tone issues in the B2RE head.

Tags: bass, american, modern, high-wattage, solid-state.

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.