Up through 1955 the amp was labeled as the Champion 600.

In 1955, the name underwent and update to The Champ Amp and the model became the 5D1. Fender designated this model as the 5E1 until 1956 when it listed as the 5F1 model. This amp underwent some changes from the prior models.

dating fender champ 12-63

The tweed material covering the amp lasted through 1964 when it changed to the familiar black tolex. From 1955 until 1963, the covering was dark brown material. A 6V6GT became the power tube and a 12AX7 filled in as a preamp tube.

Fender changed this to white/silver/black woven material in 1964. This added an additional watt to the power rating, bumping it up to 5 watts.

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.

By 1964, Fender amplifiers underwent a total redesign to what is known as Blackface models.

The control panel and inputs moved to the front of the amplifier to allow easy access for the player.

This lessens the load on the power tubes and makes the amp run more efficiently.

The Champ has but one 6V6 power tube and therefore a phase inverter tube is unnecessary.

Cranked up and miked, these amps sound like a 50-watt Marshall. Most Fender amplifiers come with two to four power tubes and operate in Class AB mode.

This means the amp comes with a phase inverter tube (usually a 12AX7) that oscillates the power between the two power tubes, or two pairs of power tubes in high watt amps.

The tubes are glued to their bases to prevent rattling.