Problems with my bass's wiring, please help!

[ForbiddenWytch]

Hey!

I've recently set about modding a P/J bass to also have a neck humbucker (a dual blade style humbucker, the Entwistle X3) that I can use as a standard pick up or as a subwoofer . I have done the body mods to the bass and have the pick ups installed.

The way I have it wired is to have the P&J pick ups going to a 3 way Les Paul style switch then off to the bridge volume on a Jazz Bass style wiring with the neck volume being for the humbucker in the neck position. I haven't put a tone control in so basically it goes from the bridge volume (or P/J volume) to the output (with just a kill switch in-between). On the neck volume pot (or Humbucker volume), I have installed a Push/Pull pot which when in the up position, I wanted to be a treble cut for that neck humbucker so it's just pumping low end only. 

Now, as said, I have done this wiring and the P/J section works great, the 3 way switch does as it should and the neck volume works as it should until you pull up the knob for the tone cut. When you pull it up, it cuts the tone from the neck pick up but also cuts the tone from the P/J pick ups too which is not what I wanted. I have attached the wiring diagram that I have used below but crudely used paint to show the changes, hopefully this works!

*edit* since trying this first method, I have swapped the centre and right lug (as if you were holding the pot pointing upwards) around and this just causes the neck volume to control the P/J pick ups too basically meaning both volumes have to be on full for the P/J pick ups to work

Can some one help me with what I need to do for this to work? If there's no simple one then I'm just going to scrap the push/pull pot and put a mini toggle switch with a tone cut between the pick up and the neck volume.

Thanks!

[Grangur]

Firstly, a subwoofer is a bass speaker. So there is no way a pickup is going to do that.

Your diagram is confusing too, because you have 1 pickup in the diagram representing 2 actual pickups. You also appear to be confused about how the connections on a switch work.

What I would suggest could be a good way to wire your pickups is to have them wired as p& j, but have a switch over to replace the p with the humbucker when you want a deeper muddy tone.

If you're unsure about the wiring , you could drop a PM to @KiOgon

@KiOgon makes great harnesses an will make your dreams come true.

[ForbiddenWytch]

Okay, sub woofer, woofer pick up, one word mix up there. Clearly I'm not asking for a pick up to act as a speaker. I was phrasing like Yamaha do in relation to the woofer pick up on Billy Sheehan's basses.

2ndly, the diagram is labelled to show that the neck jazz in the photo is there to represent the neck humbucker and the bridge Jazz is there to represent the P&J pick ups.

As I said, everything works apart from the fact the tone cut on the push/pull is cutting tone from the other pick ups as well as the humbucker in the neck when pulled up. Everything else is wired exactly as shown in the diagram and works as it's meant to. That is the only small issue. 

I don't want to run it where I switch between the neck pick up and P pick up, the 3 way switch works to switch between the P & J just fine. The neck humbucker being on 1 volume and the P & J being on the other works perfectly too. The killswitch I've wired in works as it should, earthed perfectly too so it's dead silent. The tone cut is the only issue I'm having.

[Grangur]

Ok, so Yamaha a also wrong in their terminology and I didn't know that.

All you need to do then, is wire the switch correctly so the wires are on the right terminals. Do that and you'll be fine. 

Why have you got a capacitor across bridging those 2 terminals? As you know, that won't work.

I could help, but with your attitude you're on your own.

[Woodinblack]

Unfortunately on a passive bass wiring there is no way to do what you want. 

The capacitor moves the high frequencies down to earth when you bring it in line, but there is no difference between the high frequency from one pickup from one than the other - the capacitor is there regardless, it doesn't matter physically where you put it, only electrically.

the only way you could do it is by putting a resistor in line with the pickup, but that would reduce volume badly and still let some tone bleed off.

[ForbiddenWytch]

My attitude? Okay dude? I wasn't being crappy at all so I apologise if that's how it came across but pot calling the kettle black and all with your own reply there.

I would actually thank you for mentioning about the capacitor needing to be moved to the right lugs on the switch but as said, your reply was quite rude.

[ForbiddenWytch]

6 hours ago, Woodinblack said:

Unfortunately on a passive bass wiring there is no way to do what you want. 

The capacitor moves the high frequencies down to earth when you bring it in line, but there is no difference between the high frequency from one pickup from one than the other - the capacitor is there regardless, it doesn't matter physically where you put it, only electrically.

the only way you could do it is by putting a resistor in line with the pickup, but that would reduce volume badly and still let some tone bleed off.

Hi there. I can see where you're coming from over the tone bleed etc and the earth being where the high frequencies are sent to but to mention one I mentioned earlier, Billy Sheehan's Attitude Basses are all passive and the neck "woofer" pick up has a push pull tone cut just for that pick up alone and then it all feeds off to the P Pick up volume and out put so there must be a way somehow. I might look up one of the Yamaha diagrams and see what that says?

[Grangur]

Have a watch of the video.

What you'll find is the bass has 2 output sockets. 2 on-board pre amps. You can see the battery compartment on the back.

At the risk of sounding pedantic; he never referred to the humbucker as a woofer. That said, maybe some others might do so.

As @Woodinblack says, what this bass does cannot happen in a passive circuit design. (Woodinblack knows more than I do) Form a marketing perspective, if Yamaha could make this bass passive, they would have done so they could have made it cheaper and sell more.

[Grangur]

54 minutes ago, ForbiddenWytch said:

My attitude? Okay dude? I wasn't being crappy at all so I apologise if that's how it came across but pot calling the kettle black and all with your own reply there.

I would actually thank you for mentioning about the capacitor needing to be moved to the right lugs on the switch but as said, your reply was quite rude.

Sorry if I read your post all wrong. The first was as I was hitting the sack. The second was early in the morning as I was off to work.

[ForbiddenWytch]

@Grangur Sorry again but the Billy Sheehan bass is not active at all. The compartment on the back is for access to the 2 jack inputs (they have since changed it on the Attitude III to have the jacks mounted on a plate on the front instead of the barrel jacks going through). the pick ups in Billy's basses are Dimarzio Will Power Middle & Model One Neck pick ups (passive, more recently a Yamaha designed pick up in the neck on the Attitude III but again passive). The controls are Neck Volume, Neck Tone & Bridge Volume only.

Where he talks about it being two pre amps is that he splits the signals off to 2 different wireless units and then off to 2 different amps which are sculpted for mids & highs on the P pick up then just low end on the Neck pick up. If you pull one of the pots up on his bass it actually routs all the pick ups through one output instead of two as well without cutting tone or volume from either pick up but the neck pick up will still function as that low woofer pick up. Billy's one of my main influences, I've done a lot of reading about his basses. There's also a Facebook group called "Yamaha Attitude Ltd." where a gentleman called Jon Willis built an exact replica of Billy's "Wife" Bass and tells about things like that. So in short, what I want is definitely possible with passive circuitry. It's essentially the same as with Les Pauls where you can have two seperate tone controls that don't affect the opposing pick up or like on Rickenbackers which do the same thing (and I'm not talking about the Ric-O-Sound ones here, just the standard single jack Ricks). You can run the neck pick up with the tone all the way off and still have full range on the bridge pick up or vice versa.

I'll just keep going at it on a trial and error, I have a few spare push pull pots so I'll keep going until I find a way.

[Grangur]

@ForbiddenWytch fair play. The 2 amps he referred to probably are the amp heads then.

So how this works must be by having the 2 pickups as 2 totally separate circuits wired to the 2 jacks.

If you wire them to a single jack the tone control can only influence the tone of both pups. The problem is *we* look at 2 sections of a circuit and think of them as not related and autonomous. The problem of electronics is, no matter how nicely you talk to it, it sees the bass, amp pedals etc, all as 1 single circuit.

So if, you.....

Hold on. I had a circuit once...  I had a baaa with 2 volumes an 2 tones. If worked after  fashion, but the tone control was pathetic.

[Woodinblack]

The Billy Sheehan bass wiring is on the net. There is a volume then a tone control, and a parallel tone bleed (to decrease the tone frequency) on one pickup going to a socket, and the other pickup just has volume and its own socket.

So there is no tone cut on the P pickup, unless:

There is a mono switch which shorts the sockets together. At that point the P Pickup has the same capacitance as the other pickup and the same tone cut. However, if you put them to separate amps you don't have that issue

[Ghost_Bass]

you can isolate the tone cut just to one single pickup. You need to add two resistors in there to prevent crosstalk between the capacitors. This is usually found in the old Jazzes wit 2 stacked V/T pots. I've done it on a PJ i modded a few years ago in wich i wanted independent volume and tone for each pickup, worked a treat. I don't have any schematics at hand but try googling for this type of independent tone wirings.

 

EDIT: found a pic for helping you with your seach:

 

Edited November 13, 2017 by Ghost_Bass
added pic