Bass and Guitar Double Neck Wiring

[asdmuzak]

Hi 
I've just built a double neck guitar .

Top Neck is a bass and the bottom is a guitar 
The pickups are passive and standard PBass setup with two volumes and 1 tone
The guitar has similar setup with 2 humbuckers with 2 Volumes and 1 tone.

No matter how the wiring goes to the jack output  I am unable to seperate the two necks.


I have tried  switches, no switches.

I can seperate the bass but once i connect the guitar the whole seperation goes away and the guitar volume become like a master volume for the whole guitar.

Any ideas or information would be greatly appreciated.

I took it to one of the local guitar makers and he just shook his head and said "no way mate"

I have read about stereo jacks, could this be an answer?
The other option is a neck selector with 8 connections but i'm bit of an electronics virgin to really know about these things.

Once again any thoughts/ideas would very appreciated.

Thank You 

Ian
Ian

[newey]

asdmuzak-

Hello and Welcome to G-Nutz2!

Before we can help you trouble-shoot any problems, we'll need a diagram of how you have this wired at present. It looks like a beautiful guitar!

The double-neck guitars that I have seen use a 2-pole switch (a DPDT) to switch the outputs of the two necks- each neck has a "hot" and a "ground" going to the output jack, and the selector switch simply sends one pair or the other to the jack. This way, only one neck is "on" at a time.

I can also visualize that, with a bass as one-half of the thing, one might want a separate output to go to a bass amp. A 4-pole switch could then be used to switch outputs.

[asdmuzak]

Hi thanks for your reply,
I purchased a double neck toggle switch 

Switching between guitars is no problem but the volume and tones for all of them now just stay on.
You cant really change the volume or the tone on the bass for example.

And the pickup with just tone and volume controls the volume for the soapbar pickup.?

Here is how it is wired up now.
Any help would be aprreciated. 
THis is the toggle switch which changes from guitar to bass no problems
Thanks

[newey]

The guitar has similar setup with 2 humbuckers with 2 Volumes and 1 tone.

That's not what your diagram shows. On the soapbar HB, you seem to be showing a pot used to split the coils (the so-called "Spin-A-Split"), with a single Volume and Tone after it. This seems to be a part of your problem, as the "Spin-A-Split" is then wired to the V and T controls. The wire coming out of the "Spin-A-Split" needs to bypass the V and T controls, and to be wired either directly to ground, or directly to the "hot" output (i.e., to the guitar/bass selector switch). Which way you go depends upon which coil you want to be the one that is split. (I can't tell you which one is which without knowing the pickup mfr and wiring colors.)

Also, look at how you have the V and T controls wired for the HB. You show the input to the V pot going to the clockwise lug of the pot (if looking at it from the back of the pot, which is the usual way to depict guitar diagrams). The output then goes off of the middle lug (the "wiper").

Compare that with how the V and T controls are shown for both the soapbar and for the bass side of things. There, the input to the pots goes to the wiper instead. A volume control wired in this manner will never go to "0".

So, I would suggest rewiring all of the controls just like you have the HB wired.

Finally, on the bass side of things, you do show individual V controls for each pickup, with a master tone. Since you don't seem to have a switch to switch pickups on/off, I assume you're using the V controls to turn the pickups on/off. Apart from rewiring the controls, as discussed above, you may want to consider using a dual-gang pot for the master tone; this allows each pickup to have a separate "gang", and avoids interaction between the 2 volume controls. JohnH has a thread in the Schematics section called "Strat with 2 Volumes" that describes the problem of the control interaction, and the solution using a dual-gang pot for the "master" tone.

[asdmuzak]

Newey, Thank you so much for your reply.

You have no idea how helpful this is.

I have been making guitars for a quite a while now and this has really had me stumped.

I'm getting my head around this and i'll let you know how i go.

With my other guitars i have either copied or just transplanted them.

I've included a picture of some of my other weapons.

Once again Thank you, you are an absolute champion.

[newey]

Well, thanks for the accolades, but first let's see if it works! If not, you'll be free to call me a lousy SOB instead.

[asdmuzak]

Hi
Thanks for your info, I finally got it to work.
Now my next question is am i able to run active bass pickups and passive guitar pickups.
The guy at the local guitar shop who wasn't interested in helping me with the wiring said it wasn't possible.

Surely the toggle switch would just seperate the two?

Thanks 
Ian

[newey]

Surely the toggle switch would just seperate the two?

Yes, but you may get a fairly loud "pop" when you switch the active preamp into the circuit. There are ways to prevent that, but someone more knowledgeable than I will have to tell you about it!