What does "vintage" wiring on a Les Paul look like? How is it different from "modern" wiring? What are its advantages? Drawbacks?
After a little research I have found these diagrams and some info.
A little quote regarding the pickup volumes in 'vintage' Les Paul wiring:
In the original Les Paul circuit both pickups influence each other in the middle position of the pickup selector (both pickups together). When you roll back the volume on one pickup just a little bit, the other pickup is much louder than the other and if you roll back the volume down to zero, both pickups are silent.
After the 80's Gibson switched from 500k pots to 300k pots, which made the neck pickup sound, according to one user, 'flabby and lifeless.'
In a Les Paul with what that same user describes as 'the Holy Grail' of guitar electronics, the tone is slightly better, but you can hear it. It is supposed to provide a rounder, richer tone compared to any other wiring scheme. (But sadly, I personally do not presently know, as I have never had the pleasure of playing one :-( )
The way the tone and volume pots were wired is different from today's models. This is 'vintage' wiring:
And in use in the real thing:
And today's wiring sceheme:
And this is the vintage pickup diagram:
50's and modern wiring style diagram from: http://www.mylespaul.com/forums/tonefreaks/558-wiring-library.html
Quote and other pictures from: http://www.singlecoil.com/docs/paula.pdf