Dating Fender Tube Amps By Serial Number Part 1

Last Updated on Wednesday, 19 January 2011 08:26 Tuesday, 05 May 2009 12:05

Dating Fender Tube Amps by Serial Number - Part 1

Dating Fender Amps From 1990

All Fender amplifiers manufactured from 1990 onwards bear a date code that is printed on the quality assurance sticker found on the back of the amp chassis. When sound and electrical testing are completed, several sign offs are printed on this black and silver sticker. The last line contains a date code consisting of two printed or handwritten letters indicating the amp's production year (first letter) and month (second letter).

Dating Pre 1990 Fender Amps

Dating older Fender amps by serial number, on the other hand, can be a real pain, as records of the serial numbers were never kept. The challenge, therefore, is to compile so many serial numbers that Fender Amps can be dated using them. Before we describe how the challenge was addressed, lets get some basics out of the way.

Fender Amp Control Panels

Control panels on Fender amps are categoriesd as being Silverface, Blackface or Brownface. Note that these colourings refer to the control panel and not the grille cloth.

Vinyl Covering

The textured vinyl material that covers the amp is called tolex and it comes in many different colours and textures.

Tweed

The two-tone woven fabric covering many early amplifiers is called tweed. In teh good old days, this fabric was varnished to make it more durable.

For this bit, I'm going to hand you over to the amazing article on Dating Fender Amps by Serial Number that Greg Gagliano wrote. I'll summarise the main findings here, but you really should check out his excellent article.

Greg Gagliano contacted many Fender collectors and dealers to request information he could use. This obviously turned out to be a long and laborious project. The amp serial data was collected and added to a database with records in the form of:

• Model name
• Model number on the tube chart
• Date code letters on the tube chart
• Speaker codes (only if the speaker is original)
• Transformer codes (used if the amp doesn't have date codes on the tube chart)
• Cosmetic features (whether the logo is flat or raised, tweed/tolex, blackface/silverface, rough/ smooth blond tolex, white/skirted knobs, TV-front/wide-panel, etc.)

During the project, he discovered something very interesting regarding the date code letters on the tube chart. In the autumn of 1965 Fender stopped stamping these numbers in black ink and started using green. The codes used in 1965 all began with the letter "O". Moving forwards, the code for 1966 is "P". However, some bright spark at the Fender factory forgot to change the stamper from "O" to "P" in the January of 1966. This means that Fender amps from January 1966 display the date code "OA" (A for January) in green ink. By February, Fender had disovered their faux pas and corrected the mistake. This is easy to deduce as February amps display "PB" in black as the date code.

Here is another interesting discovery concerning the control panels. When Fender were bought by CBS in January 1965, there was still a surplus of control panels that display "Fender Electric Instruments" in stock for different models. These pre-CBS control panels have actually been seen on Fender amps as late as August 1965. Champs and Vibro Champs, however, are the exception as they had foil stickers on the back of the chassis. These foil stickers appear on amps even as late as 1966. The new panels that were produced ater he CBS takeover were used from April 1965 onwards, and now said "Fender Musical Instruments". Thus, if you have a January 1965 amp, it will have "Fender Electric Instruments" written on the control panel, and if you have a January 1966 amp, it will say "Fender Musical Instruments".

Turning our intention to the steadily growing database of serial numbers, we can see some patterns emerging that will help us date our amps.

Early amps such as Woodie and Tweed have serial numbers handwritten on the tube chart. It seems that these serial numbers are used sequentially, regardless of model. Similarly, the brown/blonde Tremolux, Concert, Vibrasonic, Twin, Pro, Super, Vibrolux, Showman, Dual Showman, and Bandmaster also used a sequential numbering system independent of model, but as with Fender guitars, these were not used consecutively.

Some amps adopted their own numbering system. The 1956 to 1960 Vibrolux, the 1956 to 1964 Bassman; the 1956 to 1963 Champ, Harvard, Princeton, Deluxe, and all the tube reverb units have their own numbering scheme. The following prefixes are seen in the respective serial numbers:

• Champ - "C"
• Harvard - "H"
• Princeton - "P"
• Vibrolux - "F"
• Deluxe - "D"
• 4x10 Bassman - "BM"
• piggyback Bassman - "BP"
• reverb units - "R"
• tweed Super, Pro and Bandmaster - "S" (sometimes)

Blackface and silverface amps produced late 1963 to 1980 usually display serial numbers beginning with "A". It seems that these serial numbers did not run sequentially on all models. There are examples of serials being duplicated between models. One example is the serial number A00121 being found on a November 1964 Champ and also on a February 1965 Vibrolux Reverb. These anomalies make any patterns we establish ... a little shaky. What does seem apparent, though, is that models sharing a chassis may also share the same serialisation scheme. The Bandmaster Reverb and Super Reverb, for example, share the same chassis. Similarly, the Twin Reverb, Quad Reverb, Dual Showman Reverb, Vibrosonic Reverb, and Super Six all share the same chassis.