Ampeg VL-503 - Channel 3 preset

Verified · 87/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The VL-503 is the three-channel member of Ampeg's early-1990s all-tube VL series. Channel 1 has volume, high, mid and low; channel 2 adds gain, master and a mid-boost switch; channel 3 has gain, master, a three-way frequency switch and its own EQ. Optocouplers handle switching, each channel sets its own reverb level, and a pair of output valves with an EL34/6550 selector feeds slope, presence, a power attenuator and a recording out.

Tags: american, crunch, multi-channel.

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.