Wiring design help needed pls!

[choppy]

Hi all, I'm very new to the circuit design and wiring thing and have FA understanding tbh... I'm trying to figure it out, have read various posts etc. But I do have a couple of questions I'm hoping some of you learned people might be able to help me with please?... And even better, correct my diagram if it attaches to this thread, or post a wiring diagram to assist me... Asking a lot I know, but if I can build a successful project then I know I'll get a bit more involved in it, and I'll no doubt learn better from it too

I want to make a Frankenstein instrument using 2 guitar pickups with a 3 way switch (or a blend/balance pot would be better) and tone and volume controls, but also add in 2 Piezo pickups with their own 3 way switch (or blend/balance pot) and tone and volume controls. So essentially 4 pickups in total... But with a single output jack.
I'll attach a diagram of it lets me...
I'd like to have the options of A, A+B, or B... And also C, C+ D, or D... And then blend these combos of A, B, C and D into my output.
I hope to then blend the guitar pickups and the Piezo pickups (so yet another blend pots) to come up with a range of sounds.
Question is... If I am running the output from the guitar pickups to the output jack, and also running the output from the Piezo pickups to the same terminal on the output jack, will the 2 volume controls work okay to blend the guitar and Piezo pickups? I have read that I may need to 'decouple' the volume pots?? I haven't worked out how to do that yet...
Or will the common connection there on the output jack terminal cause issues, like the guitar pickups feeding a signal back into the Piezo pickups etc or one volume right down giving birth signals a path to ground and muting them? Should I put a blend/balance pot or something w between the guitar pup's output and Piezo pup's output and the output jack?
I'm hoping my diagram will attach, because hopefully someone can scribble on there the correct wiring for my project!
Thanks all, and sorry for the newbie complications 😉
Choppy

[choppy]

I can't seem to attach my diagram. Happy to email it through to any helpful geniuses... My email is [e-mail]

[newey]

choppy-

Hello and Welcome to G-Nutz2!

You are having trouble posting an image becasue you can't directly link to an image, it has to be hosted elsewhere. Here's a tutorial on using the "post image" button to do this. There is also a button for using Cloudinary to upload images, which most of us use, it is free but does require setting =up an account. The "Post Image" button does not require setting up an account.

Your wish list is a long one, and you may, in the end, want to cull it somewhat. For starters, a piezo pickup doesn't sense the strings in the same way that a magnetic pickup does. I doubt there is any real utility in pairing two of them together, it probably won't sound much different than a single piezo alone.

Also, a piezo pickup typically needs a preamp, which makes mixing it with a passive magnetic pickup signal a somewhat fraught enterprise, unless the mag signal is likewise preamp'd/buffered. JohnH's thread on "Adding a Piezo Pickup" tackles these issues, and should be required reading before we go much further along, as some of your ideas may change.

You may find it a whole lot easier to buy a commercial piezo system like the Ghost Saddles and just install it as specified, then you only have to work out the mag pickup wiring. Another option would be to run 2 output jacks, one for the mag, one for the piezo output, and the 2 then get combined in a buffered footpedal with A-B switching.

[choppy]

Thank you for your reply!
Yeah I can imagine my idea is likely fraught with problems... It is an idea for a percussive stomp box. Essentially having the 2 Piezos of different sizes and locations (large diameter in the middle of the timber, small diameter on the edge) to produce deeper and also high tones and being able to choose and blend those. Then having the guitar or bass pup's located under the centre and edge of a metal plate on the top of the box (I saw a tutorial where someone did this and used an old car licence plate to build his stomp box), to again get another range of sounds and tones. May not be viable to mix all these pickups in one stomp box, but if it is then I want to have a go and see what it's like Not sure if the outputs from the piezos and the guitar pups also would be too different... But I was planning also on running the output through an external preamp.
My rough initial idea was something like this: /1QD5PNB

[choppy]

Try link again /1QD5PNB

[choppy]

Again/1QD5PNB

[choppy]

Whole link not showing sorry
Maybe it will let me this way... ibb(dot)co/1QD5PNB

[newey]

Did you look at the tutorial I linked to?

OK, so a percussive stomp box. That is something I have built, and have some experience. Although I didn't try any mag pickups.

But I did experiment with 2 piezo elements, located at different points on the inside of the cigar box I was using. Using 2 piezos didn't make any difference, and I did try it with a blend control, briefly, before just simplfying things down -one piezo with a volume control. I got the most realistic kind of bass-drum sounding "thump" by dampening out the cigar box with some poly upholstery batting, loosely packed inside. Ran it through a bass amp with the EQ stack turned all the way down to "0".

But don't let me stop you from experimenting. I'll see if I can find the thread from when I was building this, it was about a dozen years ago or so.

[newey]

Here's a link to what I did. guitarnuts2.proboards.com/thread/4989/wooden-stompbox

[choppy]

Thanks again for your reply yeah I had a look at the tutorial link you posted, very interesting and good to see the possibilities, but a bit beyond my capabilities... I'm brand new to the idea of building circuits... Ideas with no real knowledge of how to implement them I guess the idea of me posting was to see if it was not too hard to achieve if at all possible, or even if with some research it was possible for me to achieve... I guess it would be but with more time needed than I can currently manage. So I really appeciate your input on your own stomp box building, it will probably save me a lot of time, expense and frustration! At this stage I will opt for Piezo only. At least to get me started. I wonder if you know, would 2 piezo's give a stronger output? And would they be in series or parallel? They might even give a bigger range of tones too if I use one larger diameter Piezo and a smaller diameter one. One last thing, could you suggest a value for the volume pot given the lower output of Piezo pickups? Would a typical 250k volume pot cut it?
And thanks again, I don't have a great understanding of electronics but I will have fun building it

[choppy]

Great post
My thinking has been pretty similar. I like the idea of a speaker cone... I can see another project in the making haha. Which way would you mount the speaker? Cone up or down? And would you fix the cone end or the magnet end to the box?

[newey]

No ideas on using a speaker cone, you would be the guinea pig on that. I used a 250K pot. I tried 2 piezo elements, in both series and parallel, at varied locations in the box (top, sides, further apart) and heard no difference. That may be the size of the box, though- a bigger separation, I suspect, would give a different sound if the enclosure were big enough to permit it.

[choppy]

Okay cool, thanks. The box will be a decent size... For typical use as a foot stomp box, but also big enough to sit on my lap and drum with both hands. So placement and how each Piezo is attached, foam cones from the top piece of the box to the top of the Piezo (if mounted on the bottom) etc, or even a spring in between to play around with the compression of the Piezo... will all be experimental I'll try 2 piezos of different diameters in this way, in parallel, each with it's own linear volume pot with each then running to the output jack... And see what happens!