Sunn 190B preset

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

The Sunn 190B is a sturdy, clean-running tube bass head from the Oregon company. Two inputs feed a two-stage 12AX7 preamp with Lo Boost and Hi Boost switches, a Volume, and passive Treble and Bass controls. A 6AN8 pentode gain stage and triode cathodyne inverter, with feedback from the 16-ohm tap, drive two 6550s in fixed bias with a bias adjust. The supply is silicon diodes with a choke and standby, and outputs cover 4 and 8 ohms.

• Made in: USA
• Channels: 1
• Preamp tubes: 1× 12AX7, 1× 6AN8
• Power tubes: 2× 6550

Tags: american, vintage, bass, 6550.

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.