National-Dobro Model 50 preset

Verified · 85/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The National-Dobro Model 50 is a 1940 five-tube amplifier. A 6J7 pentode preamp and a 6N7 phase inverter drive a push-pull pair of 6V6G output tubes, with an 80 rectifier and a field-coil speaker socket. Volume is its only control.

• Made in: USA
• Wattage: 10W
• Channels: 1
• Preamp tubes: 1× 6J7, 1× 6N7
• Power tubes: 2× 6V6G

Tags: american, vintage, 6v6.

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.