What tubes does the Ampeg V4B Preamp (1971) - Channel One use?

The Ampeg V4B Preamp (1971) - Channel One uses 3× 12AX7 preamp tubes.

When was the Ampeg V4B Preamp (1971) - Channel One produced?

The Ampeg V4B Preamp (1971) - Channel One was produced 1971–1980.

Ampeg V4B Preamp (1971) - Channel One preset

Verified · 82/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The Ampeg V-4B preamplifier section is a bass-voiced circuit derived from the V-4 guitar amplifier platform, using cascaded 12AX7 gain stages with a bass-optimized tone stack offering bass, midrange, and treble controls. Unlike the guitar-oriented V-4, the V-4B preamp omits reverb and tremolo in favor of a cleaner gain structure optimized for bass fundamentals and touch-sensitive dynamics. The V-4B preamp's musical overdrive character at moderate drive settings has made it a favorite of rock and alternative bassists who want tube saturation short of the SVT's full output tube power.

Years produced: 1971–1980
Made in: USA
Channels: 1
Preamp tubes: 3× 12AX7

Tags: american.

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).

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