Ampeg B-12X Portaflex - Channel 2 preset

Verified · 90/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The Ampeg B-12-X is a Portaflex-format two-channel amp from Linden, New Jersey. Each channel has Guitar and Accordion inputs, 6SL7 stages and its own Bass, Treble and Volume, plus a shared stereo input. A 6SL7 phase-shift oscillator and 6SN7 modulator give footswitchable vibrato, and a separate echo unit with 6SL7 stages, Dimension control and a single-ended 6V6 feeds a satellite speaker. A 6SL7 inverter drives two 6L6s off a 5U4.

• Made in: USA
• Wattage: 30W
• Channels: 2
• Preamp tubes: 5× 6SL7, 1× 6SN7, 1× 6V6
• Power tubes: 2× 6L6

Tags: american, vintage, 6l6, vibrato, reverb, two-channel, mid-wattage.

Schematic-derived preset files for the Neural DSP Quad Cortex and 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.