What tubes does the Ampeg B-12X Portaflex - Channel 1 use?

The Ampeg B-12X Portaflex - Channel 1 uses 3× 12AX7 preamp tubes and 2× 6L6 power tubes.

When was the Ampeg B-12X Portaflex - Channel 1 produced?

The Ampeg B-12X Portaflex - Channel 1 was produced 1963–1968.

Ampeg B-12X Portaflex - Channel 1 preset

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

The B-12X Portaflex is a 12-inch speaker flip-top bass combo with extended treble response. Channel 1 delivers warm, punchy bass tone with slightly brighter character than the standard B-12N. The X designation indicates a modified tone circuit optimized for bass guitar amplification with improved high-frequency extension.

Years produced: 1963–1968
Made in: USA
Wattage: 22W
Channels: 2
Preamp tubes: 3× 12AX7
Power tubes: 2× 6L6

Tags: bass, american, vintage, low-wattage, clean.

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.