What tubes does the Harmony H306 use?

The Harmony H306 uses 12AX7 preamp tubes and 6L6 power tubes.

When was the Harmony H306 produced?

The Harmony H306 was produced 1962–1967.

Harmony H306 preset

Verified · 88/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The Harmony H306 is a mid-range combo from the early-to-mid 1960s with a push-pull output stage providing more power and cleaner headroom than the single-ended student models. It features a simple tremolo circuit typical of the era and a warm, articulate clean tone. The H306 was suited to small ensemble playing rather than pure home practice.

Years produced: 1962–1967
Made in: USA
Wattage: 14W
Channels: 2
Preamp tubes: 12AX7
Power tubes: 6L6

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.