Marshall Club & Country Bass 4150 preset

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

The 4150 is the 100-watt compressor bass model of Marshall's late-1970s Club & Country range. Bright, Stereo and Normal input jacks feed an ECC83 stage with a FET compressor (Compression Width and Ratio), then one Volume with a Hi-Mid Boost, a recovery stage, and Treble, Bass and Middle with Mid Sweep. An ECC83 long-tail inverter with Presence drives four EL34s (6550s on US units) via a 4/8-ohm output.

• Made in: UK
• Wattage: 100W
• Channels: 1
• Preamp tubes: 2× ECC83
• Power tubes: 4× EL34

Tags: british, bass, el34, high-wattage.

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.