Dual source pickups on acoustic guitar.

[Rob-H]

Hi there,
I'm new here, I play fingerstyle on my Epiphone jumbo acoustic. I've just bought the LR Baggs M1 passive soundhole pickup which I want to fit permanently - it comes with an endpin jack. I'm also going to fit a JJB330 transducer pickup under the soundboard - I haven't received that yet but it's on its way in the mail. For recording purposes I'm wanting to run each signal onto it's own separate channel via my two channel preamp - no problem there. What I'm more concerned about is having two jack/output holes drilled in my guitar.
I've read bits about dual sources wiring onto one end pin jack and was wanting some information or guidance on this. I had a look at the wiring configuration on the passive M1 jack and from memory there is a red wire, a white one, and the shield also seems to be connected. Can anybody confirm this? Here's a pic I took.

I'm not quite sure what to expect from the JJB330 when it arrives, but assuming it has a similar configuration, does anybody know how I could go about wiring these two sources to one jack socket which will then split the signals on output?
I mean, if it can't be done so easily it's not the end of the world if I have to drill a second hole but the convenience and asthetic side to having one output is obvious. There are no other knobs, switches or preamp features on the guitar, just the two passive pickups.
Thanks
Rob

[Steve Conner]

Like many other end pin jacks, the one in your picture is stereo. I imagine the ring contact is used to switch the power to an active preamp inside the guitar. Since you have passive pickups, you don't need power switching, so you can use the ring contact to output a second signal. Then use something like this to break it out: Hosa Insert Cable Stereo 1/4" to Two Mono 1/4" at zZounds

Wiring wise: Each of your pickups should have a shielded output cable, with one core and a screen. Connect the cores of the two cables to the two tabs on the jack where the red and white wires in your picture are. Connect the screens of the two cables together to the jack's large ground tab.

When used with a regular mono guitar lead, you'll get the output from one of the pickups.

Edit: From the LR Baggs manual: "The prewired strapjack harness has stereo output capability. You can connect the output wire from a mini-mic or another transducer to the ring
terminal of this jack. Then run a stereo cord to the L.R. Baggs Mixpro or your favorite outboard gear."

[Rob-H]

Like many other end pin jacks, the one in your picture is stereo. I imagine the ring contact is used to switch the power to an active preamp inside the guitar. Since you have passive pickups, you don't need power switching, so you can use the ring contact to output a second signal. Then use something like this to break it out: Hosa Insert Cable Stereo 1/4" to Two Mono 1/4" at zZounds

Wiring wise: Each of your pickups should have a shielded output cable, with one core and a screen. Connect the cores of the two cables to the two tabs on the jack where the red and white wires in your picture are. Connect the screens of the two cables together to the jack's large ground tab.

When used with a regular mono guitar lead, you'll get the output from one of the pickups.

Edit: From the LR Baggs manual: "The prewired strapjack harness has stereo output capability. You can connect the output wire from a mini-mic or another transducer to the ring
terminal of this jack. Then run a stereo cord to the L.R. Baggs Mixpro or your favorite outboard gear."

Thanks, Steve
that's extremely helpful and very well explained. That picture attached is the actual end pin from my Baggs M1. I didn't know about that ring wire being being used for power switching to internal preamps. So in my photo I presume I have TRS - Red (tip), white (ring), screen (sleeve) - i think. And If I am right in thinking, I should leave the red wire (tip) as it is, connect my other pickup JJB330 to where the white one is (ring) and then the two shields on the longer tab (sleeve). So if my JJB330 SBT comes with a similar wiring output, what do I do with the white wires if the ring is going to be used for the second pickup?
Sorry for so many questions. Thanks again and also for the heads-up on that output cable
Rob

[Steve Conner]

It's unusual to see a passive pickup with three wires. I assume in this case it's because the same "strapjack harness" (as LR Baggs call it) is used for the active and passive versions of the M1.

This being the case, I wouldn't expect your JJB330 to come with the same wiring, but if it does, you can assume that one of the wires does nothing and wire it up as you described.

With one caveat: I wouldn't be so sure that red corresponds to tip and white to ring, I'd want to check it with a meter. (or touch the tabs and listen for hum)

[Rob-H]

Thank you kindly,
I hope to report back when I've set it up and let you know how it went. Great advice.
Rob

[Rob-H]

Just out of interest for anybody else that is working on the Baggs M1, I had it confirmed by the manufacturer techy that the red 'hot' wire comes attached to the tip of the strap jack and the white is attached to the ring. It would appear, as Steve rightly said earlier, that the ring is used for power switching to internal pre-amps. To test the theory I disconnected the white wire and the passive M1 pickup still works
I'm just waiting for my other passive to arrive now to solder it onto the ring and I should be fine.
for info