The Fender Prosonic guitar amplifier was produced by Fender Musical Instruments from 1996 to 2002. The Prosonic featured several departures in design from traditional Fender amplifiers such as the Bassman, Twin Reverb, and Deluxe Reverb. Designed by Bruce Zinky as a project for the Fender Custom Shop, the amplifier later had a non-Custom Shop production run at the Fender facilities in Corona, California.
The Prosonic introduced several features that had previously been seldom, or never before, seen in Fender amplifiers. Its most unusual feature is the switchable rectifier and power amplifier bias scheme, allowing on-the-fly changes of operating mode and output power (as well as subjective tonal differences). This feature, originally found on Randall Smith's Mesa Boogie amplifiers, allows the Prosonic to achieve a versatility very rarely seen from mass-market instrument manufacturers. The Prosonic's rear-mounted RECTIFIER/BIAS switch lets the user select from the following three options:
1. Solid-state rectification with fixed bias (marked "S.S. AB2"). Listed at 60 watts R.M.S.
2. Tube rectification with fixed bias (marked "AB2"). Listed at 50 watts R.M.S.
3. Tube rectification with cathode bias (marked "A"). Listed at 30 watts R.M.S.
A channel-switching amp, the Prosonic offers a clean channel that features a blend of traditional Fender sounds with the influence of Vox amplifiers, frequently attributed to the Class A mode. Many players praise the Prosonic's clean channel as being "softer," and more prone to break-up and musically desirable distortion, than more contemporary Fender designs. Detractors view this trait as an apparent "darkness" in tone, and perceive this lack of the typical Fender "sparkle" as merely an undesirable lack of clean headroom.
The Prosonic also brought levels of gain (distortion) previously unavailable in a Fender amplifier. Taking a major cue from the first generation of Mesa Boogie amplifiers such as the Mark I (itself a modified Fender design), the Prosonic used additional gain stages in the preamp section that cascaded into one another.
This amplifier is in great cosmetic and operating condition. I has been tested thoroughly in-house and works great.