Ampeg Pre-Amp Duette / Dolphin II - Pentode Channel preset

Close · 65/100 confidence. Most values readable. Minor gaps filled by inference from similar circuits.

The Pre-Amp Duette/Dolphin II is a very early Ampeg preamp from the mid-to-late 1950s, documenting Triode Channel operation. These early preamps represent Ampeg's formative years before the company established its guitar and bass amplifier product lines. A historically significant piece of early vacuum tube amplifier design.

• Years produced: 1955–1960
• Made in: USA
• Channels: 2
• Preamp tubes: 2× triode

Tags: american, vintage, preamp, 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.