After all this time, there still is some confusion out there on what
"point-to-point" wiring really means. I thought I'd do a little show and
tell and try and shine some light on the matter.
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).
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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.
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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.
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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.
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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.
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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.
I'm fond of Turret boards myself, but any of the first four methods listed
above will work and sound fine, and are about equal in reliability.
The first four also look like they were hand-crafted. There's
something beautiful about a pristine Hiwatt interior that makes you want to
show it off. Do you ever see people selling TSL Marshalls, Rolands and
Peaveys on EBay showing pictures of the "guts"? No - it's about as exciting
as looking at your computer motherboard.
Here are some pictures illustrating some of the classic amps and their
methods of construction.
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A Sunn Sorado (point to point)
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Another look at the Sunn Sorado (point to point)
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A Fender Super Reverb (tag board)
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A Marshall Super Lead (tag board)
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A Vox AC10 (unusual tag board)
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A Hiwatt (turret board)
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A Hiwatt (partial PCB)
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An early Marshall JCM800 (Partial PCB)
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A Fender Blues Jr. (total PCB)
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