Ampeg SVT-350H preset

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

The Ampeg SVT-350H is a 350-watt solid-state bass head of the late 1990s whose power amp board is shared with the B-2. That board carries an effects send and return, preamp out and power amp in jacks, and a balanced XLR line out with pre/post and -20 dB switches, then an optocoupler limiter with an LED ahead of three pairs of IRFP240/IRFP9240 MOSFET outputs on plus and minus 60-volt rails, with a fan and speaker relay.

• Wattage: 350W
• Channels: 1

Tags: american, bass, solid-state, high-wattage.

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.