National-Dobro Model 50 - Main preset

Verified · 83/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The National-Dobro Model 50 is a pre-war American tube guitar amplifier from National-Dobro of Chicago, one of the pioneering firms in electric guitar technology. Produced during the formative years of the electric guitar industry, these amplifiers represent some of the earliest purpose-built guitar amplification equipment available commercially. Original examples are extremely rare and of enormous historical significance.

• Years produced: 1936–1943
• Made in: USA
• Channels: 1

Tags: american, vintage.

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.