Lectrolab R500 - Microphone preset

Verified · 91/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The Lectrolab R500 is a late-1950s American tube combo from the catalog-sold Lectrolab line, the first in the range with a push-pull output. Two instrument inputs share one 12AY7 triode and a mic input has the other, each channel with its own Volume, mixed into a 12AY7 gain stage and a paraphase phase inverter. A pair of cathode-biased 6V6GTs with a single Tone control and a 5Y3GT rectifier give a warm, simple American clean.

• Made in: USA
• Wattage: 10W
• Channels: 2
• Preamp tubes: 2× 12AY7
• Power tubes: 2× 6V6GT

Tags: american, vintage, 6l6, clean, two-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.