Copyright 1997, 20th Century Guitar Magazine.

Boy, that title got your attention didn’t it?  Well, we’ll get to good parts, but first a little background information is in order.  After reading Teagle and Sprung’s excellent Fender amp book, I took them up on their challenge that maybe someday someone will compile enough serial numbers so that Fender amps can be dated that way.  So began my quest.  I contacted several Fenders collectors and dealers who were kind enough to supply me with data.

I turned to the Internet to do some more networking which resulted in a major turn of events as I met two individuals who have become instrumental partners in this project:  Greg Huntington and Devin Riebe.  Greg is a long time Fender collector who is very knowledgeable not only in the details, but in the circuitry as well.  His particular area of expertise is in Fender amps made from about 1960 through 1967.  Devin runs Doc’s Music in Springfield, Missouri and his interest lies in the woodie and tweed Fender amps made from 1946 through 1960.  Greg and Devin’s experience meshed well with mine since I’m essentially the blackface/silverface amp guy (amps made between 1963 and 1980) in the group.

Additionally, Greg and Devin also had data that they had been collecting from Fender amps for years.  We combined all of our information into a computerized database for this project and for the past 18 months have been slowly (sadly, very slowly) gathering information that we collect ourselves as well as from other people.

Now it’s time for a commercial.  We need your Fender amp data!  Everything is confidential, we don’t make record of who owns what amp in the database.  What we need is the following:

1) Model name
2) Model number on the tube chart
3) Date code letters on the tube chart
4) Speaker codes (if speaker is original)
5) Transformer codes (if the amp doesn’t have date codes on the tube chart)
6) Cosmetic features (flat/raised logo, tweed/tolex, blackface/silverface, rough/
   smooth blond tolex, white/skirted knobs, TV-front/wide-panel, etc.)

One very interesting and very important factoid has surfaced regarding the date code letters on the tube chart.  In the fall of 1965, Fender switched from stamping these numbers in black ink, to dark green ink.  These 1965 codes begin with the letter “O.”  The code for the year 1966 is “P.”  However, someone in the factory apparently forgot to switch the stamper from “O” to “P” in January 1966.  Therefore, amps from January 1966 have the date code “OA” (A denotes January) in green ink.  The factory realized its mistake in February because these amps have a “PB” date code in black ink.  Now, we obviously haven’t looked at every amp made in January 1966 so this isn’t set in stone.  If anyone has an amp with a “PA” stamp, please let us know.  Still, I wouldn’t be too quick to just glance at that tube chart and accept an “OA” as a January 1965 amp.

 The biggest tip off would be the control panels which brings us to interesting factoid #2.  After CBS bought Fender in January 1965, there were still plenty of control panels for various models that were in stock.  These say “Fender Electric Instruments.”  Depending on the model the use of these pre-CBS panels have been observed on amps as late as August 1965, except for Champs and Vibro Champs which had foil stickers on the back the chassis.  Fender must have had a million of these labels printed up since they appear on Champs and Vibro Champs well into 1966.   New panels made after the CBS acquisition were used beginning in April 1965 and say “Fender Musical Instruments.”  So, if you have January 1965 amp, it will have a Fender Electric Instruments panel whereas a January 1966 amp (even though it has that green “OA” date stamp) will have Fender Musical Instruments.

Okay, now on to the dating-by-number stuff.  Although the database doesn’t have thousands upon thousands of entries, we are seeing some interesting patterns emerging that will help date amps by serial number.  Some of the trends are really obvious.

The early amps (woodie and tweed) had serial numbers handwritten on the tube chart.  These appear to be used sequentially independent of model.  Likewise, the brown/blonde Tremolux, Concert, Vibrasonic, Twin, Pro, Super, Vibrolux, Showman, Dual Showman, and Bandmaster used a sequential numbering independent of model, but as with Fender guitars, these were not used consecutively.

Some amps had their own numbering system.  The 1956 to 1963 Champ, Harvard, Princeton, Deluxe; the 1956 to 1960 Vibrolux,  the 1956 to 1964 Bassman, and all the tube reverb units have their own serialization scheme.  The Champ has a “C” prefix, the Harvard an “H” prefix, the Princeton a “P” prefix, the Vibrolux a “F” prefix, and the Deluxe a “D” prefix.  The 4x10 Bassman used the prefix “BM” while the piggyback Bassman used the prefix “BP.”  The reverb units have the prefix “R.”  In addition, the tweed Super, Pro and Bandmaster sometimes have the prefix “S” in the serial number.

The blackface and silverface amps  (late 1963 to 1980) generally have serial numbers begin with the prefix “A.”  However, it appears that these were not used sequentially across all models.  Our evidence is that we are finding some serial numbers duplicated between models.  For example, serial number A00121 has been found on a Champ dated November 1964  and a Vibrolux Reverb dated February 1965.  This makes things a little more interesting and difficult in playing the “dating game.”  And yet there is another variable to contend with as it appears that models that share chassis may also share the same serialization scheme.  For instance, the Bandmaster Reverb and Super Reverb share the same chassis, and the Twin Reverb, Quad Reverb, Dual Showman Reverb, Vibrosonic Reverb, and Super Six all share the same chassis.

Preliminary results show that we’re on the right track.  Here’s a couple of examples using the tweed Deluxe (model 5E3) and the Super Reverb/Bandmaster Reverb.

Ser No.           Model                       Year
D05108          Deluxe                      1958
D05160          Deluxe                      1958
D06528          Deluxe                      1958
D07036          Deluxe                      1959
D07115          Deluxe                      1959
D07418          Deluxe                      1959
D08325          Deluxe                      1959
D08913          Deluxe                      1959
D09014          Deluxe                      1959
D09338          Deluxe                      1960
D09399          Deluxe                      1960
D09524          Deluxe                      1960

A27769          Super Reverb            1967
A27796          Super Reverb            1967
A29591          Super Reverb            1968
A31057          Super Reverb            1968
A31079          Bandmaster Reverb   1968
A32839          Super Reverb            1968
A32841          Super Reverb            1968
A34448          Super Reverb            1968
A37667          Super Reverb            1969
A37949          Bandmaster Reverb   1969
A40130          Bandmaster Reverb   1969
A41569          Super Reverb            1969

So, with the knowledge gained thus far, we feel that Fender tube amps can be dated by serial number.  We just don’t have enough data to make any definitive conclusions yet.  So please... send your amp data to the author c/o TCG Magazine or by e-mail to ggjaguar@aol.com.  We will be writing articles in the future with more fun factoids (yes, there’s more!) with new information on dating by serial number.  Thanks for your support!

The author and his partners would like to thank those people who have sent us Fender amp information, especially James Werner, Tim Pershing, Gregg Hopkins at Vintage Amp Restoration, Jim Strahm and Matt Kesler at Midwestern Musical Co., and Tim Nelson at Mass Street Music.  Also thanks to the many dealers at the various guitar shows that we visit for allowing us to make notes about the amps at their booths.