Making a piezo pickup

[David M.]

no "mando" content, but pickup content...

Got a piezo film to use under my bridge foot on my fiddle.

below is the piezo and below that is the jack that a music store buddy gave me. notice the piezo cable has 3 wires: copper; white; red (the copper and white were soldered together from the place I ordered it from).

which wire goes to which lead on the jack? there is a short lead, longer lead, then the real long lead that has the pointy things on it.

Another question: can I cut some of that long lead w/the pointy things shorter so I can screw the cover closer to the end? right now it's going to leave about 3/8" of threads showing because it won't screw all the way to the wood block I'm using for the jack holder (Carpenter style clamp).

thanks,

[David M.]

Below is the pic of the jack...

[mandroid]

from Musix I got one of his piezo discs, it was the Piezoelectric crystal bonded to a disc of brass. one lead went to be soldered to the crystal itself, the other one to the brass disc, then I made it durable with a bit of epoxy and hotmelt glue keeps the Cable #secure. it/ they work.
[got 3 , overheated one, soldering onto the Crystal, #, so I have 2 that work]

Electrically, #generally pattern red is the hot (+) lead #that would go in this case #to the tip contact, the center tab with the little hole in it , #and the #sleeve #is the part that crimps around the wire , #solder the copper and white combo there , crimp the #thing around the insulation, #pre emptively may add some tape if it wont grip the wee insulated wire well
appears the signal return (-) and the shield #are soldered together .

a balanced 3 conductor combination , [TRS] would have the white wire soldered to #the 'ring' contact , and the copper braid to the ground or sleeve contact .
but this is a 2 contact jack . I presume.

so first , perhaps you have to make a hole #in the instrument rim? to put the jack into? or is this an external setup? #carpenters jack.. #not Karen ...

clean surfaces well , and some electronics soldering flux is needed, a dab on the end of the thing [wire] being soldered flows first, keeps it and the surface being joined #clean while its being heated by the soldering iron, to the solder's melting point. #don't dawdle , if iron is hot enough it should be quick,
overheating messes things up.

good luck.. if you havent soldered anything before , practice on other stuff first , naturally..

[EdSherry]

I'd suggest that you (a) see if you can find information from the manufacturer of the piezo film as to what the various wires are (hot, ground, etc.), (b) figure out how you intend to wire the jack (TRS vs. TS -- yours looks like a standard 2-conductor TS), © figure out what each connector on the jack is supposed to be (hot, ground, etc.) and (d) wire it up accordingly. #

The hard step is (a).

[ErikAitch]

And yes, you can shorten the lead; 1/8" of tinned conductor should be plenty. And yes, do practice on junk first.

[David M.]

Just contacted the piezo mfg. by email. we'll see what he says.

I'm making a carpenter type clamp from a pc. of old birdseye maple and violin chinrest clamps.


(b) figure out how you intend to wire the jack (TRS vs. TS -- yours looks like a standard 2-conductor TS),

I don't know what TRS or TS means. is that mono vs. stereo?

I'm an acoustic player and NEVER dabble in electronics, really of any kind http://www.mandolincafe.net/iB_html/non-cgi/emoticons/sad.gif , so forgive the dumb questions. And, thanks for help.

[thistle3585]

That is a 1/2" flush mount stereo jack. I use them all the time. Wire the two wires that are soldered together to the longest stem, and the other to the shortest stem. Yes you can cut the prongs back on the jack. There shouldn't be too much concern about overheating the piezo while soldering to the jack but a 25 watt to 30 watt soldering iron is suggested to prevent damage.

[jefflester]

(b) figure out how you intend to wire the jack (TRS vs. TS -- yours looks like a standard 2-conductor TS),
I don't know what TRS or TS means. #is that mono vs. stereo? #
TRS = Tip-Ring-Sleeve. It can either be for a balanced line or for stereo. If you look at headphone plugs, either full size or mini, that's TRS. A simple mono/unbalanced 1/4" plug or jack like a normal instrument cable is TS - Tip-Sleeve and just doesn't have the extra ring in the middle.

http://www.soundinstitute.com/images/tt70f8.gif

[mandroid]

FWIW, Overheating not an issue in soldering wire leads anyhow, My project was more DIY, and cheap, a raw piezo wafer disc on a piece of brass, minus any wire , this looks a snap..
most is already done ..

[Joel Glassman]

Where did you get the piezo from?

[groveland]

a raw piezo wafer disc on a piece of brass, minus any wire

FWIW, I just did a piezo thing (http://www.mandolincafe.net/cgi-bin/ikonboard.cgi?act=ST;f=16;t=40745;st=50), DIY, over in the CBOM board on a bouzouki. Doesn't help with the current wiring question, but it does, I think, demonstrate you can go a long way with the basic element, and it's fairly hard to mess it up...

[mandroid]

David M , or me? , I disclosed the source of mine , the Cub , he called it, mine from Musix,com were remainders ..
I made mine up as temporary stick ons with a short bit of Mic cable
and a radio shack 1/4" female connector .. http://www.mandolincafe.net/iB_html/non-cgi/emoticons/wow.gif

[Smyers]

Yuck! #Not a radio shack 1/4" connector. #Say it isn't so! #What you want is one of these:

Neutrik 1/4" mono female panel connector (http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=092-126)

or

Gold mono/stereo Switchcraft version (http://www.guitarelectronics.com/product/JK23)

or, if you need an endpin version


Endpin jack (http://www.guitarelectronics.com/product/JK41)

You can get just about any kind of electronic jack/part for musical instruments at Allparts, but they are far from being the only supplier out there.

Allparts (http://www.allparts.com/categories.php?cat_id=550&cat_name=JACKS)

Happy connector hunting!

[groveland]

This is what I used for a jack - Very nice allen wrench tension adjustment, very solid.

http://w.emgpickups.com/display....ogid=62 (http://w.emgpickups.com/displayproducts.asp?section=Acoustic&categoryid=3&catalogid=62)