MIMF

I used a cheap piezo disc a a PU on my old Yamaha FG180 years ago. For the cost (>50cent) I was quite happy. I suspect with a preamp it would have been a lot better. I was looking at cheap discs on Ebay and was tempted to try it again. They are some variation in the specs given, resonant freq (2-7) kHz, various physical sizes (~0.5-1.0 inch dia) etc. I was wondering if any had any thoughts on which to go with.

Hi Andrew,
I don't have huge experience using off the shelf piezo disks for instrument pickups, as I usually use complete solutions, but I recommend getting one with as high a resonant frequency as possible, as this will give the flattest frequency response.
Good luck, and let us know how you go!

A few weeks ago I was informed that I had to sit in with my brothers band. I was supposed to play the mando I made a few months earlier. I had about 12 hours notice and that included learning g to play the mandolin. I got a radio shack buzzer and cut the piezo out of it and wired up a 1/4" jack. Sorry, I don't remember the specs. I even cut a big chunk of the piezo off so it would fit where I wanted it. It seemed to be too something (too sensitive to other influences I side the box?) so I hot glued a little peice of foam on the back of it. Either the glue or the foam tamed it nicely. There was a big variation in to e depending on where it was located. I ended up taping it to the underside of the sound lard in the cutaway point. I did 't have a preamp so I just plugged directly into one of the guitar player's amps. It worked well enough for the event. With more effort (and a preamp) you could probably get fairly descent results. Though it might be better to use a product designed to accomplish your goal.

Using cheap piezo disc pus are commonly used when building cigar box guitars.
I use them to amplify cigarbox guitars that my students make on a "make your own scrapwood cigarbox guitar in 5 hours" -course.
You can google on "uncle bobs guitar project", for more information installing a piezo disc.
You can also consider buying some cheap under saddle piezo pickups from ebay or aliexpress.

When everything is installed properly you can get a very workable sound.

Thanks for the responses. I've tried Ebay and higher priced (K&K) piezo pickups. They all seemed comparable to the cheapo I used back when, so for a buck plus an endpin jack I'll try again.

Andrew Porter wrote:Thanks for the responses. I've tried Ebay and higher priced (K&K) piezo pickups. They all seemed comparable to the cheapo I used back when, so for a buck plus an endpin jack I'll try again.

Let us know how it turns out.

My limited experience with the cheap piezo disks a dozen years ago; they sound surprisingly good, they last
for maybe a year or two, before the piezo layer starts to separate from the substrate and they go dead. If anyone finds otherwise- or finds a way to make them last longer- I would love to hear.

Nicholas Blanton wrote:My limited experience with the cheap piezo disks a dozen years ago; they sound surprisingly good, they last
for maybe a year or two, before the piezo layer starts to separate from the substrate and they go dead. If anyone finds otherwise- or finds a way to make them last longer- I would love to hear.

I have had some luck dipping them (usually twice) in the same plastic used for tool handles.

If you shield the leads it makes the entire piece a bit stronger as well.