Two stacked pots and no toggle

cementwave

New member
I'm in the process of building a bass and its in the final stages of completion. I bought a pair of the passive Phase II soapbar pickups for it and I want to wire them up to two concentric pots so they each have a volume and a tone. I dont want(or have room for) a toggle switch though. Anyways I would greatly appreciate some help with a couple things.

First, the wiring. I cant find a wiring diagram that has 2 volume & 2 tone without a toggle. After looking at several different diagrams I came up with this:
wiring1.jpg

Yeah, I just took two of the same picture from stewmac and photoshopped a line between them, but as far as I can tell this is what I should do for it to work. But thats just as far as I can tell and thats not saying much, so what do you all think?

The other thing I wanted some opinions on was the type of pots. I'm thinking of going with some 500k's because they're supposed to not bleed of as many highs and I like highs(tonal highs that is... I swear). I'm assuming that since these are basically humbuckers there shouldnt be any problems with this but does anyone have any knowledge to the contrary, like they'll sound super terrible or something?

Sorry for the lengthiness of my lack of knowledge, but your replies will help me out and make me very happy
 
Re: Two stacked pots and no toggle

http://www.fender.com/community/forums/viewtopic.php?t=16039


Here while its not a diagram his pictures are clear enough that I was
able to discern whats going on with the wiring. I used it to convert my MIM Jazz bass to the original Jazz bass wiring that had the concentric knobs like you want to use. As far as the pots go you should have no issues at all using 500k's Hope this helps

*edit* As a side note I cant see the diagram you linked it might be correct but i cant say... friggen chinee blocking everything...
 
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Re: Two stacked pots and no toggle

A couple of notes: With the volume pots wired like that, the pickups will "see" a 250k load. Not a problem, but you should be aware of it. You'ld need 1 meg pots for the load to be 500k.

Also, not that its a big deal, but since the tone pots are wired as rheostats, you can reverse the order of the two bottom lugs. That is, jumper wiper-to-wiper, and solder the cap against the two end lugs. Just makes the wiring "neater".
 
Re: Two stacked pots and no toggle

Now I feel kinda dumb, I had totally forgotten that the original Jazz's were wired up exactly like that. Had I remembered I would have checked to see if Fender had the wiring diagram for the 62 american vintage Jazz bass and I would have found this. Oh well. It can be helpful to see what it really looks like when you're putting electronics together so that you know you're following the diagram correctly. So the pictures that Edgecrusher found will be nice for when I'm actually wiring the thing up.

ArtieToo, thanks for the info, its very helpful. Here's a question though, how would the pickups "see" a pair of 250k pots?

Another thing I just thought about was the capacitors. I see the Jazz there has .05 on the neck and .03 on the bridge. Other diagrams for different pickups(jazz, p, etc) seem to pretty consistently be just .05. The Rics had .047. Anyways, from what I read you get less highs the larger the uf number. Do they make a huge difference? I dont feel like I've heard of that being brought up very much. Or at all. Any advice or info on this? I'm assuming its not that big of a deal, but I just want to be sure that's the case.
 
Re: Two stacked pots and no toggle

Here's a question though, how would the pickups "see" a pair of 250k pots?

As a single 125k load. Any time you have two resistors in parallel, and it doesn't matter if they're pots or resistors, the total resistance is halved. So two 250's is 125. Two 500's are 250. Two 1M's are 500k, etc.
 
Re: Two stacked pots and no toggle

Just a note worth looking at. The "62" Jazz wiring as shown on the Fender website will allow interaction between the tone controls. In other words, one tone control will affect both pickups. You can eliminate this problem by adding 300K resistors in line between the output lug of each pot and the output jack. This was done on the original 62's but not on the reissues. Works like a dream to eliminate tone control interaction.
 
Re: Two stacked pots and no toggle

In other words, one tone control will affect both pickups. You can eliminate this problem by adding 300K resistors in line between the output lug of each pot and the output jack. This was done on the original 62's but not on the reissues. Works like a dream to eliminate tone control interaction.

Thank you! That is definitely something I would want to know and will probably go ahead and do. Just to make sure I'm understanding this correctly, I would have one resistor going between the two pots and one going between the bridge pot and the jack, right? Also, which lugs are the output lugs on the pots?
 
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