What tubes does the Harmony H410A use?

The Harmony H410A uses 12AX7 preamp tubes and 6L6 power tubes.

When was the Harmony H410A produced?

The Harmony H410A was produced 1967–1971.

Harmony H410A preset

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

The Harmony H410A is a revised version of the H410 with updated components and minor circuit changes made during the production run. It retains the same multi-speaker cabinet format and high-output push-pull design as the H410 while reflecting Harmony's ongoing engineering refinements. The H410A represents one of the final iterations of Harmony's original Chicago-era amplifier line.

Years produced: 1967–1971
Made in: USA
Wattage: 40W
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.