Fender Bandmaster

See also: Fender Bandmaster Reverb

Fender Bandmaster, model 5G7, early 1960

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.

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  Fender Bandmaster, silverface, 1968 "drip-edge" with AB763 circuit
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Timeline

Timeline gleaned from

Year	Inputs	Output	Form	Speakers	Controls	Circuit/Model	Price
1953	2 instr, 1 mic		Combo (Wide Panel) Tweed	(1) 15" + ext jack Jensen P15N	Volume, Treble, Bass	5C7	$229.50
1954	2 instr, 1 mic		Combo (Wide Panel) Tweed	(1) 15" + ext jack	Volume, Treble, Bass	5D7
1955	2 instr, 1 mic	26 watts	Combo (Narrow Panel) Tweed	(3) 10" + ext jack	Volume, Treble, Bass, Presence	5E7
April 1960	2 channels, each with high & low sensitivity input jacks	40 watts	Combo (w/Modern Fender style) brown Tolex	(3) 10" + Pulse Adj. jack	each channel: Treble, Bass, Volume Vibrato channel also: Speed, Intensity master Presence	5G7
End 1960	2 channels, each with high & low sensitivity input jacks	40 watts	Combo brown Tolex	(3) 10" + ext jack	each channel: Volume, Treble, Bass Vibrato channel also: Speed, Intensity master Presence	6G7
Feb 1961- June 1963	2 channels, each with high & low sensitivity input jacks	40 Watts	Piggyback ("head") cream rough Tolex Feb 1961-1962: Oxblood grille 1962-July 1963 gold wheat grille	(2) 12" + ext. jack Oxford 12M6-10, Jensen C12N	each channel: Volume, Treble, Bass Vibrato channel also: Speed, Intensity master Presence	6G7-A
July 1963	2 channels, each with high & low sensitivity input jacks	40 watts	Piggyback ("head") smooth blonde Tolex/black tolex (1964) Transition models had this period features with smooth blonde tolex covering/sparkle gold grille	(2) 12" + ext. jack	each channel: Volume, Treble, Bass Vibrato channel also: Speed, Intensity Presence removed, "Bright" added	AB763
1968	2 channels, each with high & low sensitivity input jacks		Piggyback ("head")	(2) 12" + ext jack	each channel: Volume, Treble, Bass Vibrato channel also: Speed, Intensity Bright	AA568
1969	2 channels, each with high & low sensitivity input jacks		Piggyback ("head")	(2) 12" + ext. jack	each channel: Volume, Treble, Bass Vibrato channel also: Speed, Intensity Bright	AA1069
1974	Discontinued	.	.	.	.	.	.

Cosmetics

• Tweed
• Blonde
• Blackface
• Silverface 1967–1974
  • Drip Edge 1967–1968
  • Black Line 1967–

Circuit notes

5C7

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.

5D7

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.

5E7

Negative feedback and filter choke added, and the output section given fixed (grid) rather than cathode bias. Phase inverter changed to cathodyne (concertina) type.

6G7 and 6G7-A

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.

AA/AB763

The AA763 (July 1963) and improved AB763 (March 1964) ("blackface") circuit is arguably considered the "best" circuit version produced for this amp by collectors and aficionados. The complex brownface "harmonic vibrato", however, was replaced by a simpler electro-optic oscillator. Power tubes were the even beefier 6L6GC. Some 1964 blackface Showmen were still covered in blonde Tolex rather than the usual black. Later "silverface" amps retrofitted to this circuitry are described as having been "blackfaced," a reference to the black faceplate used on these amps during much of this era.

AA568

The AA568 version (introduced May, 1968) was met with popular dislike by Fender's customers. It is referred to at times as the "silverface" circuit, referring to the brushed aluminum control plate used from 1968 to 1974. The circuit and cosmetic changes didn't happen at the same time; some 1967 and early 1968 Bandmasters still possessed the blackface AB763 circuitry.

Unfortunately, the tube chart inside the amp head cannot be reliably used to differentiate the AB763 from the later circuits, as Fender continued using the older tube charts for a while after changing the circuit configuration.

AA1069

Some of the changes from the AA568 were reverted in October, 1969, yielding the AA1069 circuit, but many of the changes remained in place.

See also

• Bandmaster Reverb
• Fender