Ampeg B-25B - Channel 1 Normal preset

Close · 72/100 confidence. Most values readable. Minor gaps filled by inference from similar circuits.

The Ampeg B-25B is a variant of the B-25 bass head, featuring a slightly revised circuit and cosmetics. Like its sibling, it delivers roughly 55 watts from a quartet of 6L6 power tubes, providing the warm, authoritative all-tube bass tone that Ampeg was famous for. The B-25 series bridged the gap between the intimate Portaflex combos and the massive SVT that debuted in 1969, giving gigging bassists a mid-powered tube option for smaller to medium-sized venues.

Tags: american, vintage, clean.

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.