Dating fender tube amps by serial number

10 Sep

The heavy transformers and copper chassis assembly were placed on the bottom of the amp cabinet.

An internal “umbilical cord” linked the chassis to the volume and tone controls at the amp top.

First named the “Dual Professional,” this amp was soon renamed the “Super Amp,” with two 10” silver Jensen speakers. This amp has a TV front and a 15” Jensen Alnico bluebell speaker with the choke mounted on the side.

The Dual Professional was the first to have tweed covering, a top-mounted control panel and a tube chart, which would eventually become standard for all but the smallest amp models. This example is all original with linen grille cloth and vertical wooden slats hidden underneath the grille cloth to protect the speaker.

Many years later, in the ‘80s, I was back into playing and recording and looked in the want ads for a Fender tube amp. That amp turned out to be an early-production 1960 Pro-Amp.

I started to investigate the world of pre-CBS Fender amplifiers.

The ratings were lower still (T, U, V, etc.) for 6”, 8”, PA and other small or light-use speakers.

Tweed amps can be placed in three general categories by the styling of the front of the amp: “TV”, “wide-panel” and “narrow-panel” tweed.

The tweed amps depicted below are all one-speaker combo amps – not exotic, but very desirable even today for their tone. The alnico magnet was designated by a “P” in the speaker code; thus, a P12R is a 12” alnico speaker rated “R” as to its output capability.

This amp has a silver Jensen 15” speaker and two “port” holes in the back cover to better control the diffusion of sound.

The copper chassis and upper control panel are badly corroded on this example; again, the use of copper instead standard chrome metal was a departure by Fender.