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.Fender has used only a handful of different speaker types over the years.Here’s a list of brands along with their EIA codes.The following chart, was originally printed in VG magazine, by Gerald Weber.If you see any data that is not listed here or notice any errors, for 1970’s and earlier Fender amps, please send us an email and we will update the chart.
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.
The original Fender amps were tube-powered and the company also started producing solid-state models in the late 1960s.
Most of the amps were finished in a "gray crinkle" finish.
Electronic components such as transformers, potentiometers, speakers, and some capacitors are often stamped with a date code, which indicates the manufacturer and the manufacturing date.
The code follows the format: = a number from 1 - 52 indicating the week of manufacture.