What tubes does the Ampeg M-12-A (7591 version) - Accordion/Mic use?

The Ampeg M-12-A (7591 version) - Accordion/Mic uses 2× 12AX7 preamp tubes and 2× 7591A power tubes.

When was the Ampeg M-12-A (7591 version) - Accordion/Mic produced?

The Ampeg M-12-A (7591 version) - Accordion/Mic was produced 1962–1966.

Ampeg M-12-A (7591 version) - Accordion/Mic preset

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

The Ampeg M-12 Mercury with 7591A output tubes represents a higher-powered variant of the Mercury series guitar combo. The 7591A pentode output tube was favored by Ampeg during the 1960s for its combination of power and tonal character — providing more output than a pair of 6V6 tubes while maintaining a clean, warm American sound. This version of the M-12 offered noticeably more headroom for players who needed to stay clean at higher volumes.

Years produced: 1962–1966
Made in: USA
Wattage: 22W
Channels: 2
Preamp tubes: 2× 12AX7
Power tubes: 2× 7591A

Tags: american, vintage, clean.

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