"There are five basic types of guitar amp wiring in my mind, and often two or more kinds are combined in a single unit (I'm ignoring solid- state amps, as they exclusively use the Total PCB method listed below).
Point-to-point - Each component is connected to a tube pin or solder lug or jack. There are no "boards" whatsoever. Examples of this style of construction include most old tube hi-fi equipment, 70-era Sunns, and more recently BadCats.
Tag Board - the classic Fender and "plexi" construction methods. Most components are soldered to a long board with eyelets. These are in turn connected by wire to the tubes, transformers, pots, etc.
Turret Board - The classic Hiwatt/Harry Joyce style, this is similar to tag board construction, but uses metal turrets which extend out from the board, which most of the components are connected to.
Partial PCB - Used by most modern large manufacturers starting in the late 70s/early 80s. Most components are soldered to a Printed Circuit Board, which has copper lines or traces on the underside of the board surface that the components are soldered to, and which also make circuit connections. Example of this style of construction include the early (vertical input) JCM800s, Biacrown-era Hiwatts, and Soldano SLOs. This method basically used the PCB as an advanced tag board, and many wires are still needed to connect the tubes, etc.
Total PCB - Used by most modern large manufacturers starting in the mid-80s to the present day. Everything is soldered to a PCB, including pots and tube sockets. This makes it easier and cheaper to manufacture, but harder to service and modify, and there is some question about the reliability of the PCBs holding the sockets of the extremely hot power tubes. "
A nice little bunch of info that I was reading the other day. at
http://mhuss.com/AmpInfo/.