Dating vintage fender amps by serial number
The cream-colored board is laid out entirely differently (and better) than the green board. But the old ones sound darker, while the new ones are brighter, with more emphasis on treble tones.One is not necessarily better than the other; the dark tones are nice for blues and jazz, while the new amps do brighter tones better.Other sources to date your amp may include serial numbers and overall look and visual components on the amp as well.For example, the logo on the amp or materials used during a certain time period of production.2006 amps have a small metal “Fender 60th Anniversary” button on the back plate. Early Tweeds The early green board tweed-covered amps were not lacquered. It has the same cream board inside with the same components as every other current-production Blues Junior.The serial numbers for these amps begin with “LO,” indicating that they were made in the Fender/Sunn Lake Oswego factory. It usually applies to old vacuum tubes/valves that have gone unsold for decades. All cream board tweed Blues Juniors have a “Limited Edition” plaque on the back.
Please keep in mind that those components must be original to get a valid date for a vintage guitar amplifier.
The NOS Blues Junior is a current production, lacquered tweed amp with a Jensen reissue C12N speaker. There’s nothing limited about the edition; they built a bunch and when they ran out, they built another bunch.
Other Variants The Blues Junior chassis has also been used in the Two-Tone, a large amp with a 10-inch and a 12-inch speaker.
All green board and all cream board Blues Juniors are identical electronically, despite what the salesman told you. Below is a table of revision dates and the changes made on those dates. Fender adopted a two-letter dating code in 1990, and the code can be found on the Quality Assurance label, inside the cabinet, sometimes located on the bottom, next to the reverb tank, sometimes on the side.
The codes are usually handwritten, and the letters can occasionally be hard to decipher. There is no reliable way to date 2003-2005 amps other than to ask Fender customer support to look up the date from the serial number, although you may find a date code on the speaker.