Blend Control for a 4004L

[tomg]

My BB Laredo should arrive tomorrow, so it's time to ask this question.

I thought about doing the VVT mod so I have independent volume for each pickup, but I think what I'd rather do is replace the pickup selector switch with blend control.

What would be involved in this? I'm handy with a soldering iron, so the mechanical part of the work will be easy. I'm just not sure what part(s) I'll need and exactly how it should be wired up.

TIA!

[jwr2]

I think for passive electronics 2 volumes might work better than a blend control ...I'm sure you can find a wiring diagram on the internet ...

[jps]

I also favor the VVT instead of VPT for passive instruments, due to the extra loading of the pickups going through what amounts to two volume controls for each pickup. With a pan/blend control set at the center detent the pickups are seeing a volume control halfway down/up which will affect the tone.

[tomg]

Makes sense.

Could one of you give me some info on how the 2nd volume pot gets hooked up and a recommendation for the part(s) I need to make it work?

[jps]

You want to wire it up just like a Jazz Bass:

http://fender.com/support/diagrams/pdfs/AJAZZ/SD0193400APg2.pdf

As to pots, anything that is readily available from the usual sources as long as they are 500K for the HB-1s, plus a .047uf cap suitable for tone controls. A good source for the parts is the RIC Boutique.

[cheyenne]

Keep in mind, that VVT will require a little bit of modification to the existing hole for the 3pos switch. The hole for the switch is smaller than the ones for the pots, therefor it must be drilled out slightly. Not a big deal,, but just a heads up.

I went with concentric pots in my CII.



These allow for VT\VT for each pickup, with no permanent modification. What I did was unsolder the origial controls from the pup leads and drop these in with a "dummy" selector switch. I still have the orginal controls intact, in case I want to drop them back in.

[cheyenne]

Here's the link to the pots:

http://www.stewmac.com/shop/Electronics,_pickups/Potentiometers_and_push-pull_pots/5/Control_Pots.html

You may want to consider this option. A 4004L in Blueboy is pretty rare. I dont think I've ever seen another.

[jps]

A third option would be just VV if you do not use the tone control, this way it would be similar to stock visually. A new switch could be put in that is wired up as a mute switch or a preset tone using a cap and a resistor to get the tone setting you would want with just a flick of the switch.

[aceonbass]

Could a 4004 also be wired VV with a 3 position selector switch? The pickups would go into the volume pots and then to the selector switch, like a Les Paul without tone controls.

[tomg]

So far it sounds fine as it is. If I decide to make a change, I'll want it to be reversible.

[jps]

That can work Dane.

[aceonbass]

I'm still getting a volume drop when I run both pickups together on either neck of my double neck. Since I usually run the tone controls wide open anyway, a may just rewire it VV>Selector switch for each neck.

[rickfan60]

I am planning to do the stack knob thing to my 4004C. I like the ability to blend the pickups.

[tomg]

This is gonna sound like such a noob question.

I've decided to hold onto one of my 4004L and I'm doing the VVT mod. Everything is pretty much all done, but I have one remaining question.

On the Jazz Bass wiring diagram Jeff posted above, there's no common ground wire connected to the pots nor to the ground lug of the jack.

I'm _assuming_ that I need put put in a ground that is soldered to each pot and then to the jack.

Is this correct?

[tomg]

Answering my own question:

Yes, I needed that ground wire.