Official Luthiers Forum!

Who has done it?
What mix of stuff did you use?
Any troubles during build/ installation?
How did they sound when it was all done?

_________________
"Act your age, not your shoe size" - Prince

Chris, I sort of did it - my son built a LP Jr style guitar and had me wire it (altho he's an electrician he can't solder). We installed Seymour Duncan pickups with their little coil splitting rings and a Baggs piezo ToM style bridge. We wired it to a stereo jack so he could have both signals to an A/B/A+B selector box. The Baggs has individual sensors in each saddle - they are soldered to a little PCB to combine them.







The whole idea of this was that he plays in a P&W band and didn't want multiple guitars on stage - he can switch from humbucking to single coil to "acoustic" sound.

I didn't spend a lot of time with the guitar - wired it and gave it back to him. My personal preference was the straight humbuckers (but then I'm a humbucker sort of guy). I really didn't care for the piezo bridge - it did not sound "acoustic" and had a much lower output - you would definitely want a preamp or some sort of DI box with it. However, its a pretty straight forward installation (a bit spendy tho) and does give the options of trying different sounds in one guitar.

If you're running out stereo it can be pretty simple. If you want ability to switch between or blend the two with good results through mono output though, you really need a buffer/preamp system. The simplest route in my opinion is to just get an LR Baggs CTRL-X system, and bypass the headaches of trying to MacGyver an arrangement to make a passable magnetic/piezo mix work.

_________________
Eschew obfuscation, espouse elucidation.

I have. The first guitar, and the only electric, I built has two humbuckers and a Baggs piezo ToM. They feed a preamp/blending board that I made based on plans from the MIMF. Set up with switching for blended output or stereo out to separate amps. Being a EE I geeked out and put every switching and control option I could think of on it. Works good but did not achieve the objective which was to eliminate two guitars on the stage. The acoustic sound just isn't there. Might be able to do some post-processing to improve the acoustic sound these days.
I don't play it anymore but it looks ok hanging on the wall.

_________________
Steve Smith
"Music is what feelings sound like"

I had a passive system on a prototype guitar for a while. The piezo bridge needed a much higher resistance volume pot. I just mixed it with a humbucker through a gibson 3-way switch. The thing barely worked in that the piezo tone was not very fat as it lacked a high impedance preamp. It was an interesting experiment but not worth continueing. If I was to do it again I would have two TRS (tip/ring/sleeve) jacks on the guitar (like the "insert" jack on a PA mixer) for the piezo and the magnetic. The return of the trs would go to the pickup selector switch on the guitar. TRS wires (a standard PA accessory) would run to an acoustic preamp for the piezos and effects boxes for the magnetic.
After experimenting with complex systems, I find that I can imitate the role of an acoustic guitar most effectively by having a clean magnetic pickup and turning the danged thing down!

Here's the schematic of a preamp to blend a piezo and a mag pickup. It's from the MIMF, there's lots of info in the archives there.


And here's how the preamp looks. That's a 1.5"x2.0" circuit board I designed and etched myself.

_________________
A man hears what he wants to hear, and disreguards the rest. Paul Simon

Rodger, that's the one that Vlad worked out. We modified it for my application. I'll see if I can find it - it's all in a binder somewhere. Be good to get it posted here in case someone is interested.

_________________
Steve Smith
"Music is what feelings sound like"

Right, Steve, that is one of the designs that Vlad did. There were several, and the discussions in the library are very confusing because you're never sure which design is being discussed. The original design mixed a piezo and an internal mic with only a blend control. There was also a piezo and mag with only a blend control, and both of those with a blend and volume control. There were a couple of others, I organized all the schematics, board designs, and component layouts and posted it as a single thread. It's in the MIMF library here: http://www.mimf.com/old-lib/mimf_preamp.pdf
You do have to be a member to see the archives.

_________________
A man hears what he wants to hear, and disreguards the rest. Paul Simon

I was working with Vlad in April 2001. Very cool that you pulled everything together and organized it. Circuit #3 is essentially what I used with some modifications, used two 9V batteries for extra headroom and set the circuit up to use a stereo output. One channel was blended mag/piezo and the other piezo only. A very versatile little circuit and Vlad was very much the gentleman to work with all of us who were wanting different versions of that circuit.

For whatever reason it didn't get put in the electronics archives, probably because the application was too specific and had more switching options than needed. If I ever build another electric it will be a LOT simpler

_________________
Steve Smith
"Music is what feelings sound like"

Chris - I can't address the first three, but I can comment on the last one. I used to have a PRS Archtop that had two humbuckers and an LR Baggs piezo bridge pickup (required a battery). It sounded great and what I liked most about it was that it had a blend knob to mix the magnetic and piezo pickups in whatever ratio you wanted. You could get some really nice tones using the blend control. The other controls were master volume and master tone. It had two output jacks: one was the piezo alone so you could send the signal to an acoustic amp, and the other was a mag/piezo mixed output jack. It was very simple to use. Just plug it in and play. The piezo output matched the output from the humbuckers so no issues there. If sounds at all interesting, I bet you could find out details of the circuitry and components from the PRS community.

_________________
Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

Appreciate all the input, guys!

_________________
"Act your age, not your shoe size" - Prince

Hey Chris.
Probably won't work for ya,
but I have a weissy style,
that has a baggs saddle pickup,
and a soundhole pup,
and stereo set up,
that the mag pup goes into the amp,
the saddle pup goes to a di box,
then both go into the amps 2 inputs.
The di box dials in the balance you want.
One of the best sounds I ever got!
I'm working on a similar instrument right now.
A