DATING FENDER AMPS BY REFERENCE OF SERIAL/CHASSIS NUMBERS

Dating older Fender amplifiers from before 1994 is difficult because no proper records were kept. An exact date is therefore not to define but is an approximation.

From 1990 to the present, all fabricated Fender amplifiers have a date code. This is printed on the quality assurance sticker (QA) on the back of the amplifier chassis.

Where to find the serial/chassis number
On older models, the serial number is punched on the right side of the chassis.
More recent models are have a sticker.

 title=


If you want to know the production year of Fender amplifier, you can decipher it with the serial number decoder.

Fender amplifier date decoder


Dating 1951-1969

On the inside of the cabinets of Fender amplifiers that were built after 1950 and before 1970, a sticker is generally attached. This indicates the type of the tubes used and their location on the chassis. Also on this sticker stamped two letters (sometimes handwritten) indicating a date code.



From 1990
All Fender amplifiers manufactured from 1990 until now, have a date code printed on the quality assurance (QA) sticker on the rear of the chassis. This black-silver sticker shows signatures or initials of employees after the finished noise and electrical tests.
The last line also has a stamped or handwritten two-letter date code. Handwritten is sometimes difficult to read (see image). The first letter is the year and the second letter is month.



If no QA or tube location sticker is found or it is bad read, look at the rear of the chassis on the right side where a chassis number is punched. You can decipher the year of construction using the date decoder.

Date code from 1951 to 1969 and and from 1990
Letter Code Vintage year Retro year Month
A 1951 1990 January
B 1952 1991 February
C 1953 1992 March
D 1954 1993 April
E 1955 1994 May
F 1956 1995 June
G 1957 1996 July
H 1958 1997 August
I 1959 1998 September
J 1960 1999 October
K 1961 - November
L 1962 - December
M 1963 - -
N 1964 - -
O 1965 - -
P 1966 - -
Q 1967 - -
R 1968 - -
S 1969 - -

Some indications that you can also recognize the production year.
Before the CBS era (before 1965) Blackface amplifiers were feature labeled Fender Electric Instrument.
Blackface amplifiers from 1964 and some from early 1965 did not have the Fender logo on the grill cloth.

After the acquisition of Fender by CBS in January 1965, amplifiers were labeled as Fender Musical Instruments.

From 1974 a potentiometer with pressure-pull switch was added to some amplifiers.

The logo on the grill cloth of the amplifier also gives an indication of when it was produced.
A logo with tail is from before 1973. After 1973 the logo was tailless. With few exceptions. As long as there was a stock with tail logos, they were used randomly in 1973.
Amplifiers from that year and perhaps also in 1974 can therefore have the new or old logo.

tailless (after 1973)      with tail (before 1973)

There are a number of amplifiers from '68 and '69 announced, including the Vibro Champ and Bassman, which also had a tailless logo. However, these logos are made of plastic and slightly smaller than the metals.



Dating of components

If there are no sticker or chassis number at all, the the components can also offer a solution for dating the year of construction of the amplifier. (Assuming the transformer is original and has not been replaced.)

Transformer
With help of the EIA (Electronics Industry Association) number on the transformer, the production date can be determined. This is not the production date of the amplifier, because the transformer has already been made before and may have been for a while in storage.

The EIA number on the transformer which Fender has used the most starts with 606, followed by 3 or 4 digits. 606 is the manufacturer (Woodward-Schumacher), but a transformer from another manufacturer may also have been used. (see component list)
With 3 digits, the first digit is the last digit of the decade of the 20th century. The last two digits is the week of that year. At 4 digits, the first two digits are the year of the 20th century. Example: 606 6849 is 1968 week 49. If the production date of the transformer is now known, add at least 6 months to the production date of the amplifier. From the example, the amplifier could have been built in 1969.

Transformer date decoder

Speakers and potentiometers
What applies to the transformer also applies to speakers and potmeters.

Speaker date decoder
In the 1950s, Fender mainly used potmeters from the Stackpole brand (304). Halfway through 1963, the switch was made to the CTS brand (137). In 1967 Fender bought a very large stock of CTS. This delivery took more than five years. Amplifiers (and also guitars) made in 1973 can therefore still have the 1967 potmeters with EIA numbers from the stock that was purchased in 1967.
(see also Potentiometer decoder)

Fender used Jensen speakers until 1972.
In that year the Jensen production was transferred to Rola. (Rola was already a part of Jensen). When Rola started making speakers for Jensen in 1972, Rola also used Jensen's EIA code in the beginning (220). At the end of 1972, Rola changed the code to 285.



Component list and manufacturer
Manufacturer Code Component
Altec-Lansing 391 Speakers
Cleveland 433 Speakers
CTS 137 Potentiometers, Speakers
Eminence 67 Speakers
Electro Voice 649 Speakers
JBL 73 Speakers
Jensen 220 Speakers
Oxford 465 Speakers
Pyle 1098 Speakers
Rola 285 Speakers
Stackpole 304 Potentiometers
Triad 830 Transformers
Utah 328 Speakers
Woodward- Schumacher606Transformers


Please note, old Fender amplifiers may look old, but are not. For example, speakers, potentiometers or transformers may have been replaced,
or the coating of the amplifier/cabinet is renewed (re-tolex).

Tolex is the flexible and waterproof vinyl material with which the cabinet or amplifier is covered. These 'adjustments' do not have to have an adverse effect on quality, provided that the electronic components have been replaced with the correct values and requirements.

Production period Fender models
  Model   Introduction    Discontinued
Bandmaster 1953 1974
Bandmaster Reverb 1968 1980
Bassman 1952 1977
Blues Junior 1990
Bronco 1967 1981
Champ 1948 1982
Concert 1960 1965
Concert II 1980 1987
Deluxe 1948 1966
Deluxe Reverb 19641979
Harvard 1955 1963
Hot Rod Deluxe 1996
Hot Rod DeVille 1996
Princeton19491979
Princeton Reverb 1964 1981
  Model   Introduction    Discontinued
Pro 1946 1965
Pro Junior 1993
Pro Reverb 1965 1982
Prosonic 1996 2002
Showman 1960 1993
Super 1947 1963
Super Reverb 1963 1982
Tremolux 1955 1966
Twin 1948 appeared in several variants until 2012
Vibrasonic 19591964
Vibrolux 1964 1982
Vibro Champ 1964 1982
Vibrosonic Reverb 1972 1982
Vibroverb1963appeared in several variants until 2008
White Amp 1954 1962