This is the classic 50's SG wiring and differs from Modern wiring in the location of the capacitor. There are many ways to wire a Tone Cap and the way the tone cap connects between your pots changes how the Volume Pots and Tone Pots interact with each other. The main advantage of 50's wiring is that there is less trebble loss as you roll down the Volume.
With ’50s Wiring, the tone cap connects to the middle lug of the Volume Pot, and Lug 3 of the Tone Pot.
Pros of ’50s Wiring:
The pickup tone stays consistent when turning down the Volume Pot.
Pickups don’t lose high frequencies when turning down the Volume Pot.
High frequencies tend to stay clear with the Volume Pot in its lower ranges.
Cons:
Turning down the tone pot can affect the pickup’s volume.
Some high-gain situations can yield an overly bright tone.
With Modern Wiring, the Tone Cap connects to the Input Lug of the Volume Pot.
Pros of Modern Wiring:
The Tone Pot will not affect your pickup’s volume.
A smoother tone in general, which some players like.
Cons:
Turning down the Volume Pot will send some high frequencies to ground, darkening your tone.
