Although his job was somewhat limited, his recollections provided some really fascinating insights to how the amps were built.These units look, and apparently sound, just like the Schumacher-made units so it’s easy to overlook that “831” code.Working at FMI – I was able to interview a fellow (who wishes to remain anonymous) who worked at Fender in 1972-73 in the amp department. I promise the tables will still be there after you finish reading.
A 1957 tweed Vibrolux was reported with a tube chart printed with circuit “5E3” (tweed Deluxe) instead of the correct 5F11 (see photo).
Clearly Fender wasn’t afraid to use incorrect parts when they were in a bind. The 5G12 Concert is the earliest version from very late 1959 and early 1960 so the existence of a tweed example, while extremely rare, is certainly plausible since Fender was making lots of tweed amps during the same time period.
These are marked with EIA code “831” and are most prevalent during the 1966-68 time period.
Some examples include a '66 Princeton Reverb and ’66 Pro Reverb with Better Coil output transformer, a ‘66 Deluxe Reverb and ‘67 Twin Reverb with Better Coil reverb transformer, and a 1968 Vibro Champ with Better Coil trannies.
These are marked with EIA code “606” which is the company number for Schumacher.Well, this universal “truth” was debunked when we found a bunch of amps with transformers made by the Better Coil and Transformers company.