Kay 703 preset

verified · 90/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The Kay 703 is a tiny practice amp built on radio-style lines, rated for 117 VAC only: a 12AU6 pentode preamp drives a single-ended, cathode-biased 50L6 beam tube, with series-wired heaters and a 35Z5 rectifier fed from a small transformer, for around 2 watts. Three inputs feed the preamp, followed by a tone control (with the power switch on its pot) and a volume. It distorts almost immediately, which makes it a lo-fi recording favorite.

Tags: american, vintage, practice, low-wattage, breakup.

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.