A documented circuit is one moment in a line that ran for decades. This section places each amp in its family — the chain of revisions it came from and the ones that followed — as a dated, sourced era timeline. Most entries are history-tier: the model is placed and cited but its circuit isn't drawn yet. A few link straight to the fully documented circuit page. 16 lines, 97 models, 39 with a documented circuit.
The Deluxe is Fender's mid-power workhorse:
For its first fifteen years the Princeton was, in Fender's own framing, a Champ with a tone control and a slightly larger output transformer:
The Super is Fender's two-10-inch, 6L6-powered step above the Deluxe.
Fender's smallest student amplifier and its longest-lived circuit idea:
Fender's mid-size single-15" workhorse, sitting between the Deluxe/Super class and the piggyback Bassman/Twin/Showman class for its whole run.
The Bassman began in 1952 as a companion for the new Precision Bass — a single-15" tweed combo meant to amplify a bass guitar cleanly.
Gibson built amplifiers to sell guitars, and it built them its own way.
The Twin is Fender's flagship:
A short and unusual line.
Valco was a contract shop that happened to own famous brands.
Jennings Musical Industries built its first guitar amplifier at the end of the 1950s:
Ampeg's answer to the problem of carrying a bass rig:
Marshall's first amplifier adapted a Fender tweed circuit for a British market wanting more volume, then diverged from it fast:
The Deluxe Reverb is the blackface spin-off that eclipsed the amp it grew from.
Silvertone was not a maker.
Dave Reeves trained in electronics in the Royal Air Force and worked at Mullard; made redundant in 1966, he set up Hylight in September of that year and built amplifiers under contract for Ivor Arbiter's Sound City shop.
History-tier entries record a model's place, era, tube complement and the change that defined it, with sources — but no redrawn schematic, verified operating point, or parts list yet. Those are the documented circuits, earned one at a time. Want to move an entry from history-tier to documented? Here's how to contribute a circuit.