Pre-CBS, Fender Electric Instruments, about 40 watts from two 6L6s, great tremolo.Transitional cosmetic, blonde tolex and blackface circuit. Fender's top of the line piggyback amp, blackface AB763 circuit, 85 watts, 4x6L6, solid-state rectifier, 2 channels, tremolo, matching cabinet with JBL 1x15" loudspeaker, clean and original including tilt-back legs, sliding...Numerous design changes followed, resulting in at least 13 revisions and variations on the 1176.Most units include the revision letter with the serial number.So, here I am, writing about the history of some old gear, the Silverface Fender.
Serial number 3648, original Jensen P12R alnico magnet speaker, just reconed.
If you are not familiar with working on vacuum tube equipment, you should consult an experienced technician before opening any equipment containing vacuum tubes. The Free Information Society will not be responsible for any injury or damage caused to you or your equipment.*** Early Silverface Logo on Standard Silverface Grillcloth So, you've heard all of your guitar playing life, whether it be for 2 years or 25, that you don't want a Silverface Fender amp.
I can't say today that they are the "best kept secret", because over the past few years, the prices on them are steadily climbing..obviously, the secret has gotten out.
Design Date: 6/20/67 Serial Numbers: 101-125 Faceplate is brushed aluminum with blue paint and red power light Original 1176 designed by Bill Putnam for broadcast use, class A design Signal Preamp: Used FET (field effect transistor) in a voltage divider configuration for gain reduction, a technological first Used FET as voltage variable resistor to control the gain Used ‘T-pad’ resistive attenuator to drop the input voltage Input Stage used a 600 ohm input transformer Used FET followed by bipolar transistor as preamp Output amp used essentially the same circuit as in the preamp, but followed it with a 2N3053 operating in class A Output transformer was the UA-5002; this transformer has split secondary, tertiary winding for negative feedback, emitter winding; the design was basically that of the 1108 preamp A Weston meter is used Design Date: 11/20/67 Serial Numbers: 125-216 Changed several resistor values in signal pre-amp stages; this improved stability as well as noise Circuit added bypass cap around the resistor feeding the gain reduction FET to improve stability Design Date: Not indicated Serial Numbers: 217-1078 Replaced FETs in the signal pre-amp with bipolar transistor (2N3391A) Tapped off of the emitter of the first transistor in the input stage; this provides a replica of the input voltage to the voltage variable resistor Design Date: 1/9/70 Serial Numbers: 1079-1238 Faceplate is anodized black Low noise ‘LN’ circuitry was added in the signal preamp; this reduces DS voltage on the gain reduction FET and keeps the FET within its linear range Modification to program dependency tuning Trimpot added to feedback circuit of audio FET, to minimize distortion The LN circuitry was built in a module that was encased in epoxy to protect the circuit A Modutec VU meter is used, with two lamps mounted above Design Date: Not indicated Serial Numbers: 1239-2331 Adds "UREI" branding to existing Universal Audio branding The LN module was no longer used and the circuit board was redesigned to accommodate the LN circuitry on the main board Design Date: 3/15/73 Serial Numbers: 2611-7052 Output amplifier changed to a push-pull (class-AB) configuration from the original class-A design Output transformer is changed to the B11148 type with 12 d B of gain (same transformer as the LA-3A) Push-pull design provided more output drive, and was based on the 1109 preamp Changed the metering circuit to an op-amp following the meter FET, instead of balanced bridge transistors Design Date: Not indicated Serial Numbers: 7652- 8000 Faceplate is brushed aluminum with red “Off’ button; this is the only revision with a blue UREI logo Removes Universal Audio branding VUi meter is changed to Modutec "light box" type, with two internal lamps Design Date: 6/04/08 Serial Numbers: 001-500 Faceplate is black anodized with blue paint Unique Rev.
A/E “hot-rod-mod" features, cosmetics and sonic signature Return to program dependency of legendary “Bluestripe” Rev.