What tubes does the Lectrolab R300 use?

The Lectrolab R300 uses 12AX7 preamp tubes and 6V6 power tubes.

When was the Lectrolab R300 produced?

The Lectrolab R300 was produced 1957–1963.

Lectrolab R300 preset

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

The Lectrolab R300 is a step-up model in the Rowe International Lectrolab line, offering more output power than the R200 in a similar compact combo format. Like all Lectrolab amplifiers, it was produced primarily for OEM customers — instrument brands and retailers who relabeled the chassis under their own names — resulting in the same circuit appearing under a wide variety of cosmetic identities. The R300's tube complement and circuit topology are closely related to those of contemporaneous Harmony, Silvertone, and various house-brand amps.

Years produced: 1957–1963
Made in: US
Wattage: 12W
Channels: 2
Preamp tubes: 12AX7
Power tubes: 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.