Humbucker Wiring Question

Hello.

I’m wondering about how the capacitor is wired on this tone pot. It looks to be “Modern” wiring to me, but I don’t understand why both legs of the capacitor are connected to the tone pot

Any input would be most appreciated!

Thanks

Joe

Volume to cap to pot to ground is electrically the same as:
Volume to pot to cap to ground.

Most Fenders connect the cap the way yours is wired. Gibson usually does it the other way. It's mostly convenience based on how the controls are laid out, but some of it's just habit -- Gibson started wiring it one way and keeps doing that, Fender started the other way and keeps doing it that way.

Absolutely no difference in tone or response. Works exactly the same way either way.

That is "modern" wiring, but not because of the capacitor.
Modern wiring connects the tone pot to the pickup side of the volume pot.
50s wiring connects the tone pot to the switch (output) side of the volume pot.

Faceman said:

Hello.

I’m wondering about how the capacitor is wired on this tone pot. It looks to be “Modern” wiring to me, but I don’t understand why both legs of the capacitor are connected to the tone pot

Any input would be most appreciated!

Thanks

JoeView attachment 885655

Click to expand...

I wired my 76 LP Standard to 50s wiring where the capacitor (.022) is wired like the image below. Not sure what is going on with the way the capacitor is wired in your picture.

Faceman said:

Hello.

I’m wondering about how the capacitor is wired on this tone pot. It looks to be “Modern” wiring to me, but I don’t understand why both legs of the capacitor are connected to the tone pot

Any input would be most appreciated!

Thanks

JoeView attachment 885655

Click to expand...

So I guess you are used to seeing the cap sitting between the input or output terminal of the pot and the input of the tone control; but this is only one way of wiring it.

At it's simplest, a tone control of this type is just a low-pass filter. Because a capacitor has a low impedance to high frequencies and a high impedance to low frequencies, if you stick a capacitor across the signal and earth path, frequencies above a certain level – determined in part by the value of the capacitor – will short to earth, so only low frequencies will be seen by the input of the amp. Putting a variable resistor in series with the cap limits the flow of high frequencies to earth, allowing you to change the threshold at which high frequencies short to earth.

if you look at the way the pot is wired, the cap is still between the signal path and earth, but the active part of the variable resistor's track is between the signal path and the cap rather than the other way round. Because it's a simple serial configuration of two passive components it doesn't really matter much which way round they go.

If you are wondering why a manufacturer would choose one configuration over another it's likely to be pragmatic rather than due to any consideration of tone. A tone control configured as shown can be assembled off-board and dropped in as a "unit", and manufacturers love anything that can be treated as a prefabricated unit.

The alternate configuration, where the tone cap bridges between the volume pot and the tone pot is perhaps trickier to install, but saves on that inch of wire that connects the volume and tone pots. An inch of wire saved is a fraction of a cent off the unit cost. It's a more fragile assembly, more prone to break if a pot comes loose, potentially noiser (because unless you have cavity screening then it's a length of unscreened signal path that is open to EM interference) but if you have a bumblebee or larger paper/oil cap, the size of the cap can make it easier to configure in this way.

Also, if a pot mounting nut loosens and the pot starts twisting/spinning, using the stiff legs of a capacitor can keep the loose pot somewhat in place.

The other hand is if a pot gets loose and tries to twist, using the cap to connect pots puts a lot of stress on the solder joints and the cap body. A stranded wire is more flexible and puts less stress on the solder joints (and zero stress on the cap itself).

strayedstrater said:

Also, if a pot mounting nut loosens and the pot starts twisting/spinning, using the stiff legs of a capacitor can keep the loose pot somewhat in place.

The other hand is if a pot gets loose and tries to twist, using the cap to connect pots puts a lot of stress on the solder joints and the cap body. A stranded wire is more flexible and puts less stress on the solder joints (and zero stress on the cap itself).

Click to expand...

Yep, and an old ceramic disc cap won't be long for this world if the pot loosens.

That control cavity is not going to get the Good Housekeeping Seal of Approval. Just get to cover back on before anyone gets a look.