Gallien-Krueger Backline 115 II / 210 II / 250 II / 600 - Clean preset

Verified · 86/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

This shared solid-state preamp powers Gallien-Krueger's Backline II bass combos and the Backline 600 head. It offers clean and overdrive channels with a four-band EQ, contour and boost, a master and an effects loop, all built on op-amps and JFETs.

• Channels: 2

Tags: bass, solid-state, two-channel, modern.

Schematic-derived preset files for the Neural DSP Quad Cortex and 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.