Wiring scheme for a double-neck bass w/ piezo (help, please!)

[Cernael]

So. I've got a double neck bass (5str fretted/4str fretless) for which I've gotten a set of no-name piezo bridges (like this), and now I'm pondering how to wire it all up.

The bass is pretty much akin to this one, for reference.

I'll be building [url="http://www.till.com/articles/GuitarPreamp/index.html"]Don Tillman's FET preamp[/url] to power the piezos.

Here's a start at the wiring scheme I'm considering.


The stereo pots should control volume for neck and bridge pups, respectively; the switches on the right should toggle the neck+bridge pups in series/parallel for each neck; the tone pots should control each neck. ()

Do they?

I should add some controls for the piezo unit as well; volume and some kind of tone? What do people usually have for on-board piezo controls?

I'll probably have a separate tele jack for the piezo unit, possibly with a switch to add it to the magnetic output.

Suggestions/corrections?


On another note: the intonation range on the piezo brigdes is a bit less than on the original - I've got about 1 cm between min and max settings (a few mm more if I remove the spring); how should I position them? with the max setting at exactly 86 cm from the nut (12th fret is 43 cm from the nut)? Or should I risk some mm more?

Thanks,
/Tomas

[tauzero]

I suspect you may have the same double-neck as me - H&S or Atrics, some are two fretted necks and others are fretted 5 and fretless 4. And I was thinking about exactly the same mod, using piezo bridges from some Canadian ebayer.

Will you ever want to have both necks active at one time?

Would you want to use a toggle to switch between necks or would a rotary switch do?

If you only need one active and could use a rotary switch, it gives the opportunity to simplify things by doing all the switching of the pickups first (so you select either the two pickups and piezo of neck 1 or of neck 2). That can then go to the piezo amp and to whatever volume and tone control system you're going to use - seems like an opportunity to go active with an Artec unit.

[Cernael]

Heh, yep, it's an H&S.

I was actually planning to use the stock toggle switch; closer examination shows it's a single-pole switch, though, so I guess it'd have to build one preamp for each piezo, and place them before the switch (that'll probably turn out to be cheaper than getting a new toggle switch, as they're around €6 in parts).

On another hand, no, I probably won't need to have both necks active at the same time; maybe I should replace the toggle with yet another push/pull, and use its pot as piezo volume?