N
Nigel
Guest
I used Randall Aiken's diagram for Series/Parallel (or parallel @ the jack)
It's neat b/c you can put an extra wire in there to go parallel/series.
As for the rear panel, I simply removed the switch and jacks (two plastic nuts) and put one switchcraft jack in. It's rock 'n roll.
One could use the other open hole to install a switch to go back and forth between the wiring styles.
From Jim @ Scumback on a Gearpage thread - (https://www.thegearpage.net/board/showth ... 895&page=1)

It's neat b/c you can put an extra wire in there to go parallel/series.
As for the rear panel, I simply removed the switch and jacks (two plastic nuts) and put one switchcraft jack in. It's rock 'n roll.
One could use the other open hole to install a switch to go back and forth between the wiring styles.
From Jim @ Scumback on a Gearpage thread - (https://www.thegearpage.net/board/showth ... 895&page=1)
There was a lengthy thread on this at the Metro amp forum regarding wiring 4x12 cabs.
http://forum.metroamp.com/viewtopic.php?f=14&t=17542&st=0&sk=t&sd=a&hilit=series+parallel
Here's the summary of the thread.
series/parallel wiring is darker, richer, more organic sounding for a 4x12.
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Parallel/series wiring (such as your stock 1960 A/B cab with the switch plate that does 8 ohms stereo per side, and 4 or 16 in mono) is thinner/brighter sounding with less bass response. This is the standard wiring setup that Marshall has used since the stereo/switching plates have come out. They also used it in their 4x12 cabs that had one mono input jack (JCM 800/900 to present), including their tall TV cabs.
The end result was tested by the guitarist for Starship and myself. We both came to the conclusion that the series/parallel wiring setup, with 16 gauge (or larger) wire yielded a better 4x12 cab tone than the modern setup of parallel/series.