Well, this universal “truth” was debunked when we found a bunch of amps with transformers made by the Better Coil and Transformers company.
Some things are very obvious such as non-original or reconed speakers, non-original transformers, replaced pots, re-tweed, re-tolex, re-grill, etc.
Looking at serial numbers next to the ’60 5G5 brown Pro Amp for example, we see numbers ranging from 00001 to 02000, suggesting that there are 2000 of these amplifiers made in ’60.
Since several models can share one chassis type (for example, the early brown 5G7 Bandmaster, 5G5 Pro and 5G12 Concert), this kind of interpretation is inaccurate.
Instead, there were approximately 2000 of these chasses produced, which then ended up as one of the three models in question.