Fender Vibroverb


The Fender Vibroverb was a 40-watt combo guitar amplifier originally manufactured in 1963 and 1964. It was the first Fender amplifier to incorporate on-board reverb which became a standard feature on many high-end Fender tube amps during the 1960s and 1970s.

Brownface, brown Tolex-the 1963 Vibroverb

The original Vibroverb was introduced in February 1963. The speaker lineup and the output transformer were based on the Fender Super amp of the time and the circuit based on the Fender Vibrolux of the time, with no presence control and only one 12AX7 tube for the tremolo effect. It sported typical "brownface" cosmetics, with brown "Tolex" covering, and wheat-colored speaker cloth.
The 40-watt amplifier boasted two channels. Both channels had VOLUME, TREBLE and BASS controls; the single-control REVERB affected only the BRIGHT channel.
The tremolo effect had two controls, SPEED and also INTENSITY, which affected the bias of the output tubes and therefore both channels. To make room for the reverb circuitry the company used the direct-coupled oscillator vibrato circuitry found on Fender's previous generation tweed amplifiers.
The TREBLE control was the same as found in many Fender amplifiers of the time. It was fitted with a "tapped" treble circuit, meaning that the treble control is "flat" at setting "5"; cutting or boosting the treble was possible by turning the knob down or up, respectively.
It had two ten-inch speakers manufactured by the Oxford Speaker Company.
This incarnation of the Vibroverb was made for only a few months, and it is thought that fewer than 600 of these units were made.
Tube complement:

Power:............6L6GC
Wattage?
Preamp:...........7025

Phase Inverter:...7025

Rectifier:........GZ34

Tremolo/Vibrato:..12AX7

Reverb Driver:....12AX7

Reverb Recovery:..7025

Switch To blackface, black Tolex-the 1964 Vibroverb

Fender revamped their entire amplifier line in the fall of 1963. Several models were introduced or greatly modified from their previous incarnation. The Super had two additional ten-inch speakers and a reverb circuit added; it became the much-sought-after blackface Super Reverb. The Twin was given two twelve-inch speakers and reverb; it became the legendary blackface Twin Reverb.
The Vibroverb, likewise, was given the new blackface cosmetics and somewhat different circuitry. Still rated at 40 watts, the new design possessed the new blackface "optical coupler" vibrato circuit, and a bright switch.
Gone also were the two ten-inch Oxford speakers; in their place was a single fifteen-inch speaker. Jensen speakers were used, with JBL available as an extra cost option.
Production on the blackface Vibroverb was discontinued in late 1964.
Tube complement:

Power:............6L6GC
Wattage?
Preamp:...........7025

Phase Inverter:...12AT7

Rectifier:........GZ34

Tremolo/Vibrato:..12AX7

Reverb Driver:....12AT7

Reverb Recovery:..12AX7

Historic Fame

Due to low production numbers and their use by Stevie Ray Vaughan, 1964 Vibroverbs have become highly collectable. Vaughan acquired two 1964 blackface Vibroverbs in the late 1970s or early 1980s at two different times and locations, thought to have sequential serial numbers, but were sequential production numbers. The Vibroverbs used by Vaughan were also modified by Cesar Diaz in a number of ways.

'63 Re-issue Vibroverb (1990–1995)

As demand for vintage Fender tube amplifiers had increased, several re-issue models were introduced in 1990, beginning with the tweed '59 Bassman amplifier, the brownface '63 Reverb unit and the brownface '63 Vibroverb.
Fender made great efforts to reproduce the tone and look of the original unit. A "direct-coupled" oscillator circuit was used for generating the vibrato. The noticeably "warmer" reverb sound of a vintage brownface Vibroverb was also present. The cosmetics incorporated the brown "Tolex" and wheat-colored "Ecru" grill cloth used in 1963, as well as the "flat" Fender logo plate found only on the brownface amps.
Although cosmetically and—more importantly—tonally accurate, there were several notable differences to be found. Fender used the original templates, molds and blueprints from the Oxford company archives to manufacture Oxford-style loudspeakers. The Fender '63 Reissue Vibroverb listed for $900 when it was released in 1990.
Notable users of the '63 Re-issue Vibroverb include Richard Thompson, Jeff Buckley, and the Screamin' Armadillos frontman Matt Abney.
Tube complement:

Power:............6L6WGC
Wattage?
Preamp:...........12AX7A

Phase Inverter:...12AX7A

Rectifier:........Solid State Diode

Tremolo/Vibrato:..12AX7A

Reverb Driver:....12AT7

Reverb Recovery:..12AX7A

Circuit:......6G16

'64 Vibroverb Custom (2003–2008)

Due to the continued popularity of Stevie Ray Vaughan, in 2001 Fender began collaborating with Cesar Diaz to re-create the modified 1964 blackface Vibroverbs that were used by Vaughan throughout his career. The amp debuted in early 2003.
Several modifications were made. A toggle switch mounted on the back of the amplifier chassis allows switching between tube and solid-state rectification; in the latter mode, output is boosted to 50 watts. A second toggle switch allows the player to disable the Normal channel and the Vibrato effect; the preamp gain is increased, and more distortion and sustain is available. This version of the amplifier has a fifteen-inch Eminence speaker and is hand-wired.
Tube complement:

Power:............GT-6L6 GE
Wattage:............ 50 watts
Preamp:...........12AX7

Phase Inverter:...12AT7

Rectifier:........5U4 GB USA or GZ34 or Solid State Diode

Tremolo/Vibrato:..12AX7

Reverb Driver:....12AT7

Reverb Recovery:..12AX7

Circuit:.....AA763