The Fender Tremolux was a

guitar amplifier A guitar amplifier (or amp) is an electronic device or system that strengthens the electrical signal from a pickup on an electric guitar, bass guitar, or acoustic guitar so that it can produce sound through one or more loudspeakers, which ar ...

made by Fender. It was introduced in the summer of 1955 with a rated power output of 15 watts,

cathode bias In electronics, cathode bias (also known as self-bias, or automatic bias) is a technique used with vacuum tubes to make the direct current (dc) cathode voltage positive in relation to the negative side of the plate voltage supply by an amount equal ...

, two

6V6 The 6V6 is a beam-power tetrode vacuum tube. The first of this family of tubes to be introduced was the 6V6G by Ken-Rad Tube & Lamp Corporation in late 1936, with the availability by December of both Ken-Rad and Raytheon 6V6G tubes announced. ...

output tubes, and a 5V4 tube rectifier. The Tremolux was the first Fender amp with a built in effect, tremolo."Watch Fender Tremolux Video"
Retrieved May 20, 2014. In 1957, the rated power output of the Tremolux was increased to 18 watts when it changed to a fixed bias design and a 5U4 rectifier. In 1961, the Tremolux was changed from a 1×12

tweed Tweed is a rough, woollen fabric, of a soft, open, flexible texture, resembling cheviot or homespun, but more closely woven. It is usually woven with a plain weave, twill or herringbone structure. Colour effects in the yarn may be obtained ...

-fabric covered combo amp to a piggyback amp with oxblood grillcloth, covered with cream

tolex Tolex is a trade name for a flexible, waterproof, vinyl material used as a cover material for books, upholstery, guitar amplifiers, cases, and other products. Tolex was filed as a trademark on August 30, 1945 by the General Tire, and was registe ...

. Its rated power output was increased to 20 watts, its output tubes were a pair of 6BQ5/

EL84 The EL84 is a vacuum tube of the power pentode type. It is used in the power-output-stages of audio-amplifiers, most commonly now in guitar amplifiers, but originally in radios. The EL84 is smaller and more sensitive than the octal 6V6 that was ...

(the only Fender amp of that time to feature them) and they were operated at voltages in excess of their rated maximums and under fixed bias, but was soon changed to 35 watts and a pair of

6L6GC 6L6 is the designator for a beam power tube introduced by Radio Corporation of America in April 1936 and marketed for application as a power amplifier for audio frequencies.J. F. Dreyer Jr."The Beam Power Output Tube" New York: McGraw-Hill, ''Ele ...

power tubes with a GZ34 rectifier (circuits 6G9-A and 6G9-B.) There were 10", 12" and 2×10" speaker cabinet configurations (the 2×10" being the majority of amps produced). In 1963, the grillcloth changed to gold colored. In 1964, the cream tolex was replaced with black tolex with silver grillecloth, and the circuit was changed to AB763, which used an

optoisolator An opto-isolator (also called an optocoupler, photocoupler, or optical isolator) is an electronic component that transfers electrical signals between two isolated circuits by using light. Opto-isolators prevent high voltages from affecting the ...

to couple the tremolo effect, replacing the earlier direct bias-modulation circuits. In 1963 and 1964, the Tremolux shared the same circuit as the Fender Vibrolux, with the Vibrolux being a 1x12 combo as opposed to a piggyback configuration. The Tremolux was discontinued in the summer of 1966. The early, or first Tolex-made, 6G9http://www.thetubestore.com/lib/thetubestore/schematics/Fender/Fender-Tremolux-6G9-D-FA-Schematic.pdf Tremolux Amps were the 6BQ5/EL84 amps starting at Serial Number 100. It is unknown how many EL84 style Tremolux amps were produced, but it is one of the rarest amps that Fender made and it is suspected that production totals were likely less than 300. The EL84 Tremolux did not have professionally printed tube charts, but instead they have a typewriter-written tube chart that was copied on a blue-ink mimeograph machine.

References

Instrument amplifiers Tremolux {{guitar-stub