Next, (if applicable) look for the date code on the tube chart.
The next one or two numbers are the month where January is 1 and December is 12. Example: AB763 = second revision, July, 1963 AA1070 = First revision, October, 1970 Misc Dating Info: Silver face amps with the aluminum trimmed grilles are from 67 or 69.
The fist Master volume controls were first installed in 72.
The raised “Fender” grille logo lost its tail around 76.
There are exceptions to this rule like the the Bronco.
The term “American” speakers is wide and not a very precise term.
We use it to describe a “natural” tone, meaning a relatively flat frequency response.
If possible, open up the chassis and check a few of the pots’ and capacitors’ manufacturer codes.
Remember, many components could have been changed over the years, speakers blow, caps dry out, transformers melt down, and pots wear out.
Fender installed casters on some larger amps and cabs beginning in 72.
Orange Graphic - pics and text '70s Thanks to forum member Orange at there's finally some clarity in the Oarnge serial numbers. This is of course of very good way to date your amp.
Remember, your amp is newer than the newest component.