What tubes does the Mesa Boogie Caliber .50 - Rhythm use?

The Mesa Boogie Caliber .50 - Rhythm uses 5× 12AX7 preamp tubes and 4× EL84 power tubes.

When was the Mesa Boogie Caliber .50 - Rhythm produced?

The Mesa Boogie Caliber .50 - Rhythm was produced 1987–1988.

Mesa Boogie Caliber .50 - Rhythm preset

Verified · 84/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The .50 Caliber is Mesa/Boogie's 1987 50-watt combo, slotted between the Studio .22 and the Mark III. Its 12AX7 preamp has treble, middle, bass and volume, with light-dependent-resistor switching between rhythm and lead gain from a footswitch. A five-band graphic EQ, spring reverb, an effects loop and a direct output follow, and four EL84 output tubes on a solid-state supply deliver the 50 watts.

Years produced: 1987–1988
Made in: USA
Wattage: 50W
Channels: 2
Preamp tubes: 5× 12AX7
Power tubes: 4× EL84

Tags: american, crunch, 6l6, mid-wattage, two-channel.

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.