Volume pot wiring

[mart]

When I were a lad I learnt that to wire a volume control you'd feed the hot and ground wires to the two ends of a variable resistor, and tap it to get the output, like this:


But if you google for a wiring diagram for a jazz bass, then what comes up time and again is this:

which has the volume controls wired differently, with the hot "input" going to the middle tag, and the "output" coming from one of the end tags.

Can someone explain, in words of at most one syllable, why the jazz volume controls are wired this way round?

[Ou7shined]

It's the same but in reverse.

[Dad3353]

[quote name='mart' post='1203352' date='Apr 18 2011, 11:36 AM']...Can someone explain, in words of at most one syllable, why the jazz volume controls are wired this way round?[/quote]Good afternoon, mart...
With your first wiring method, if one pot is turned down, then the other pot is also shorted to ground, so no output from either pu. With the method in the diagram (not just for 'Jazz' basses, but almost all 2-pu basses or guitars...), the wiper of the pot feeds progressively more and more to the output as you turn up, but the o/p is never shorted to ground by either.
There is no difference electrically whilst both pots are at max or min, but this minimises interaction between the volumes of the 2 pus in between.
Is this concise enough..?
Hope this helps...

[mart]

[quote name='Ou7shined' post='1203413' date='Apr 18 2011, 11:25 AM']It's the same but in reverse.[/quote]
I'm afraid you lost me there with the last word - it had too many syllables.

[quote name='Dad3353' post='1203463' date='Apr 18 2011, 12:08 PM']Good afternoon, mart...
With your first wiring method, if one pot is turned down, then the other pot is also shorted to ground, so no output from either pu. With the method in the diagram (not just for 'Jazz' basses, but almost all 2-pu basses or guitars...), the wiper of the pot feeds progressively more and more to the output as you turn up, but the o/p is never shorted to ground by either.
There is no difference electrically whilst both pots are at max or min, but this minimises interaction between the volumes of the 2 pus in between.
Is this concise enough..?
Hope this helps...[/quote]

Ahhh. This I understand. Thank you!

[mart]

And, moreover, now I understand why the volume controls on my Les Paul copy act a bit strange - they are wired the first way and, yes, if the pickup selector is in the middle position then when one volume is turned the whole guitar is turned down. It's a shame Gibson haven't learnt from Fender how to wire two pickups. But I suppose that by now it's become a "feature" of Les Pauls rather than a bug.

[Dad3353]

[quote name='mart' post='1203885' date='Apr 18 2011, 07:03 PM']...it's become a "feature" of Les Pauls rather than a bug.[/quote]
Good evening, mart...
Yes, I confirm that this is indeed a 'feature' of Gibbo's (that's how I learned..!).
Glad to have helped; sorry for the big words.