Marshall 5503 Bass 30 preset

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

The Model 5503 is a 30-watt solid-state Marshall 1x12 bass combo from 1983, built for practice and small rooms. High and Low inputs feed a 2N3819 JFET input stage and a CA1458 op-amp with Preamp Volume, then an active Treble, Middle and Bass EQ and a Master Volume. A complementary MJ2501/MJ3001 transistor output stage drives the internal 12-inch speaker at 4 ohms, with an extension or headphone output.

• Made in: UK
• Wattage: 30W
• Channels: 1

Tags: british, bass, solid-state, practice, mid-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.