Fender Bandmaster
The Fender Bandmaster was a musical instrument amplifier made by Fender. It was introduced in 1953 and discontinued in 1974. Some early models had both a microphone input and instrument inputs. Beginning in 1960, Bandmaster amps were equipped with a vibrato effect. In the 2000s, vintage Bandmaster amps remain in use by blues, Americana and rock and roll bands.
Fender Bandmaster, silverface, 1968 "drip-edge" with AB763 circuit
(back)
Timeline gleaned from
high & low sensitivity
input jacks
Vibrato channel also: Speed, Intensity
master Presence
high & low sensitivity
input jacks
Vibrato channel also: Speed, Intensity
master Presence
June 1963
high & low sensitivity
input jacks
Oxford 12M6-10, Jensen C12N
Vibrato channel also: Speed, Intensity
master Presence
high & low sensitivity
input jacks
Vibrato channel also: Speed, Intensity
Presence removed, "Bright" added
high & low sensitivity
input jacks
Vibrato channel also: Speed, Intensity
Bright
high & low sensitivity
input jacks
Vibrato channel also: Speed, Intensity
Bright
The first Bandmaster was in all respects almost identical to the Fender Pro, a dual-6L6 26-watt amp with a 1x15 speaker, with one difference: separate treble and bass controls, where the Pro like all other Fender amps to that time only had a single "Tone" knob. Like the other larger Fender amps, the Bandmaster used cathode-biased 6L6G output tubes, a 6SC7 paraphase inverter, and two more 6SC7s in the preamp with a 5U4 rectifier.
The D-series circuits represented Fender's shift from octal preamp tubes, e.g. the 6SC7, to nine-pin mini-tubes of the 12A(n)7 family, as well as the introduction of the floating-paraphase inverter.
Negative feedback and filter choke added, and the output section given fixed (grid) rather than cathode bias. Phase inverter changed to cathodyne (concertina) type.
The 6G(n) ("brownface") circuit was used in several Fender amplifiers, including the Bandmaster. It produces 40 watts into 4 ohms. The circuit was used from 1960 until July 1963 when the "AB763" circuit was introduced. "Blonde" aficionados feel this circuit has superior tonal characteristics when overdriven, to the AB763 circuit. The 6G7 and revised 7-A circuit used the long-tail pair phase inverter introduced with the 1957 Bassman, used a solid-state rather than a tube rectifier, and also included a vibrato that is heralded as Fender's best by many enthusiasts. Power tubes were now 5881s (6L6WGBs). The new model was covered in Tolex rather than "tweed;" still a combo in brown Tolex for 1960, and then a blonde-covered head-and-cab piggyback 1961-63.
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