How easy would doing this to an alembic with double p style pickups?

[jazzyvee]

I just saw a bass with this options on line and thought it's way cool. what are the pros and cons in terms of tone by doing this and would this kind of feature be possible on an alembic with dual P-style pickups?
Would you end up with tonal options that are not useful. My bass has the pickups for the E & A strings closer to the end of the neck so i think there would be quite a difference in volume between those two and the D & G strings if you selected E&A neck with D & G bridge. Interesting nonetheless.

[adriaan]

With hi-z humbucking pickups, the series/parallel switching produces distinct sounds. Your Alembic P-shaped pickups are lo-z humcancellers, not humbuckers (going by https://club.alembic.com/index.php?topic=293.0), so first of all I'm not sure if it's even possible to wire them other than stock, and if so then if it would yield similar results.

[edwin]

With hi-z humbucking pickups, the series/parallel switching produces distinct sounds. Your Alembic P-shaped pickups are lo-z humcancellers, not humbuckers (going by https://club.alembic.com/index.php?topic=293.0), so first of all I'm not sure if it's even possible to wire them other than stock, and if so then if it would yield similar results.

You can do anything you want with them because they are passive before they hit the preamp. It would involve rewiring them and using some very non-standard parts, so you'd lose the plug and play nature of the electronics, although I'm sure the mothership could accomplish this with great results.

[jazzyvee]

Adriaan, are you saying that the each of the individual 4 pickups are not in themselves hum-cancelling and each pair work as a team so the bridge two hum cancel for each other and the neck two hum cancel for each other? If that is the case then I could get hum when using one from each pair together?
But if they are individually hum cancelling then, picking up what Edwin is saying then as long as the switching is done before the preamp then that may be possible.
Just took the back off again and neck and bridge pairs of pickups have one common signal and one screen going to the connector. But then the spanner in the works is the pan pot which I think would be ok when at least one pickup from each pair is on but the risk i think is that I could switch to a combination where switch position and pan pot are at opposites so end up with no output.

Thanks for chipping in Edwin, I will be taking it to Jaydee custom guitars soon for a refinish so wondered about killing two birds with one stone. If I was stateside I would have had quite a few mods done to a number of my alembics but I don't feel comfortable sending it over to the mothership from the UK or the cost of doing that.
I guess i'm trying to get the quick tone changes on bass in a similar way that I can on my strat which to me always feels more intuitive. Maybe I should stop thinking that way and think more like a bass player. :-)

[flavofive]

Hi Jazzy,

At least based on my understanding of Activator pickups / controls, I believe it COULD be done.  I'm not an expert on Activators specifically though, so please get a 2nd opinion before altering an expensive set of pickups!

As you noted, sounds like there is only a single pair of conductors from each of the "P" pickups going back to the electronics.  To be able to separate out the "EA" and "DG" coils, you (or your tech) would need to cut the conductor that goes between the EA and DG coils, and extend these (2) new cut "ends" so that you have (4) conductors to work with for each P pickup:  EA in, EA out, DG in, DG out.

To accomplish the switching you showed, it would likely need something like a 5-position, 4-pole switch like the one here.  The switch would just turn on/off various coils, and it would go between the pickups and the controls.
I don't think this should create any conflict with the blend control.  Regardless of which coils you have "on" or "off", the blend control should continue to mix them as normal.

You're absolutely right, though, if the switch is set to neck pickup only, but the blend pot is set to 100% bridge side, you likely wouldn't hear anything!  Then again - maybe it's handy as a "both off" setting.

I actually created a bass with (5) pickups, with each one having individually-selectable EA and DG coils, and 2x volume controls like a J bass.  It's not exactly the same as the controls you're suggesting, but I think some of this is relevant.  If nothing else, the tone demos may be helpful, because I show some weirder combinations like the "outside coils in parallel" in the image you showed.

(I also uploaded a separate video to show the wiring diagram and explain how it works, which might have some useful info for you and/or your tech.)

I did make a different bass that is even more similar to what you had in mind - it has 2 pickups, and a 4-pole selector switch between the pickups and controls to select various combinations of coils.  I just haven't gotten around to making a video about it yet!  Works great though.

What might also be kind of cool with having both a blend AND a pickup selector switch is that you can do things like selecting only a single "EA" coil, and "mute" the DG strings altogether.  You can do some cool sympathetic resonance sounds that way.  I tried that in the video above - See the 12:37 mark.

Good luck!
Mike

[mica]

Actually the P pickups are not self hum-cancelling within each half - you need the pair to effect the hum-canceling. So provided you mix the opposite polarity pickups it won't be noisier than a regular P-bass (but noisier than the regular wiring). The proximity helps. If you are panned to one pickup, and only use half the coil, you'll get output, but it will hum.

[pauldo]

Mike,
That is impressive and informative, thanks for sharing.

[flavofive]

Thank you Paul!  My pleasure.

[jazzyvee]

i decided to wake up from that dream and try to find a few more gigs where I can utilise that bass more than I've had the opportunity to live before. Thanks for everyone's interest.  My brain is always looking for something different from run of the mill. :-)

[jazzyvee]

Actually the P pickups are not self hum-cancelling within each half - you need the pair to effect the hum-canceling........

Hi Mica, would that be anything to do with the my ears telling me that these pickups make the bass sound more "series like" than my AXY and MXY based basses?
Or is that "Just my imagination, once again... running away with me"......

[flavofive]

i decided to wake up from that dream and try to find a few more gigs where I can utilise that bass more than I've had the opportunity to live before. Thanks for everyone's interest.  My brain is always looking for something different from run of the mill. :-)

No worries, good luck!