Oliver B-120 preset

Verified · 90/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The Oliver B-120 is a bass amplifier from Oliver Sound of Westbury, New York, the company started by Jess Oliver, the engineer behind Ampeg's B-15 Portaflex, dating from around 1970. Two inputs feed a 6EU7 into a bass, mid-range and treble stack with U-Bass and U-Hi boost switches, then volume and a second 6EU7 stage. A 6EU7 cathodyne drives two fixed-bias 6L6GCs with negative feedback, on a solid-state rectified supply.

• Made in: USA
• Channels: 1
• Preamp tubes: 2× 6EU7
• Power tubes: 2× 6L6GC

Tags: american, vintage, bass.

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.