Jazz Bass series/parallel switch

[Cenulab]

Hi nuts,

A fried asked me about adding a series parallel switch to his Jazz Bass (American Standard), and though I've done this on a Strat, I'm not sure how the dual volume controls wouls come into play - would I be better off bypassing one of them in the series mode?

Thanks in advance!!!!

[sumgai]

Cenny,

Did you try a search on this topic? What you want's been done, so to avoid any extra finger-rash on my keyboard, let me send you here:

guitarnuts2.proboards45.com/index.cgi?board=wiring&action=display&thread=1927

and here:

guitarnuts2.proboards45.com/index.cgi?board=wiring&action=display&thread=1931

Both of those threads have links to follow for further enlightenment. And in case you're wondering, you can easily eliminate the blender pots where shown - just draw a straight wire across the wiper and non-ground terminals, and all will be well.

HTH





sumgai

[Cenulab]

Thanks, Sumgai!

I did try several searches, but came up with no results...

...and good luck with that rash! ;D

[Cenulab]

Ok - one more thing not covered in the threads so far: if the circuit still uses dual volume controls and conversion to a blend pot is not desired, would it be wise (or necessary, maybe) to disable one of the pots while in series mode, or would both pots being connected be fine?

I haven't played around with guitar wiring for quite some time, and I'm having a little trouble figuring this out...

Thanks again!

[sumgai]

Cenny,

In essence, the balance pots are simply volume pots wired across each pickup. By replacing them with a switch (a DPDT), you have an all on/all off situation..... just like a regular selector switch on a Strat, Tele, Les Paul, etc. The remaining control could be called "the master volume", that'd be a fair description.

Now, let's go backwards here - let's remove the master volume pot, and break the blend pot into two separate units - they no longer share the same shaft and knob. The wiring will now show that they are in fact wired across each pickup. If you have a switch to go between parallel and series, that switch will simply move the negative wire from one pickup away from ground, and over to the hot wire of the other pickup (said hot wire also being switched away from the output jack at the same time). But rather than re-draw everything from scratch, let's visit wolf's site, specifically his treatment of a series/parallel switching scheme:

www.1728.com/guitar2.htm

(Scroll nearly all the way down, to How It Works.)

wolf has three pickups there, ala the Strat. You can simply eliminate the Middle pup (and its switch), and the remaining diagram is exactly what you want. In fact, it's the very same thing as I added to my own Jazz Bass! ;D What you'll do is replace the switches with volume pots. Same value, same taper, it's all good. Now you're all set, eh?

In your average basement, with typical practice equipment (less than 100 watts), the tonal differences are audible, but not so impressive. In a larger venue, with a healthy amp, it's like night and day!


HTH





sumgai

[pete12345]

Apr 17, 2008 15:34:10 GMT -5 sumgai said:

You can simply eliminate the Middle pup (and its switch), and the remaining diagram is exactly what you want.

I assume we're talking about the lower of the two diagrams here. Cutting the mid pickup out of the upper diagram would not work.

Pete

[ChrisK]

Following the Series_Parallel Blend Pot w/ DPDT switch, one could just as easily use two volume pots along with the DPDT switch.

This circuit effects blending, whether thru the use of a blend [not PAN] pot or two separate volume pots.

"Upwards" is the output, "Downwards" is the signal ground.

Put the tone circuit across the output and signal ground.

Done is.

[sumgai]

pete,

Apr 17, 2008 15:34:10 GMT -5 sumgai said:

You can simply eliminate the Middle pup (and its switch), and the remaining diagram is exactly what you want.

I assume we're talking about the lower of the two diagrams here. Cutting the mid pickup out of the upper diagram would not work.

Pete

Well, the only difference between two diagrams is the labeling of the pickups. wolf did that do illustrate where to put an RWRP pickup in the chain of three pups. Remove those labels, and Presto!, same diagram, eh?

I referenced wolf's work both because it's clear and easy to understand, and to save myself the duplication of effort, yet again. I'm relatively sure that he won't mind the additional exposure. ;D

HTH




sumgai