Dating fender pots
Dating an amplifier by serial numbers can be effective as well.
Again, it's important to be sure the parts are original on the music equipment to get a valid date for the amp.
Many of these resources refer to source-date-codes located on pots or speakers within your amplifier.
Please keep in mind that those components must be original to get a valid date for a vintage guitar amplifier.
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.
Other sources to date your amp may include serial numbers and overall look and visual components on the amp as well.
There are a number of resources available online to help you to date your guitar amplifier or bass amp.
Offers a wider tone variation than standard tone controls. "Tone up" and modify your favorite guitar or bass with an S-1 Switch from Fender. Used on Vibro-King Custom, Dual Professional, and Prosonic amplifiers manufactured from '94-Present.
006-1261-000 Genuine Fender 500K Solid Shaft S-1 Switch.
Other things to look for include chasses placed in cabinets from a different year, “doctored” tube charts, non-original control plates (usually reproductions) on silverface amps, original transformer bell ends (they have correct date codes, of course) on non-original transformers, and non-original knobs (either repro or silverface knobs on blackface amps).unusual things can be found such as the empty “Pulse Adjust” hole on the rear of early ’60 brown amps, the “middle” volume control, use of tweed style grill cloth, strange non-documented transitional circuits, and changes in tolex color including the super-rare cream colored “brown” tolex that is found on some late ’60 amps. Given that people may refer to this information seeking specific production quantities of amps they are curious about, it should be pointed out that the serial numbers apply to chassis types, and not specifically to amplifier models.
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.