FBT 500 R - Channel 2 preset

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

The 500 R is an FBT two-channel tube combo amplifier with both reverb and tremolo. Each channel has its own ECC83, an ECC82 handles gain and the split-load phase inverter, and a pair of EL503s deliver about 50 W, with an ECC83 tremolo and an ECL82/ECC83 reverb circuit. It preceded the 500 R2.

• Made in: Italy
• Wattage: 50W
• Channels: 2
• Preamp tubes: 4× ECC83, 1× ECC82, 1× ECL82
• Power tubes: 2× EL503

Tags: italian, vintage, reverb, tremolo, two-channel, mid-wattage.

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.