Wednesday, July 29, 2009

DIY Piezoelectric musical instrument pickups

I have been fooling around with my new electric guitar recently and it was really fun. I have been playing the guitar since I was in Secondary 2 and that's probably too many decades than I would like to admit. All this while, I have been playing classical guitar but now electric guitars are very affordable as they are made in China. The guitar I own is made by a company linked to Gibson and the quality for the price cannot be matched. Since I am a novice, I settled for a small guitar amp with built in effects and I am hooked, spending my evenings trying to master the solo from Hotel California.

Well, long before I was hooked on bread, I was already hooked on the guitar. Since I could not find a teacher at that time, I had to learn it by myself through books. Thankfully, for the electric guitar, there is now Youtube.

Since the guitar amp is there and my daughter has been pestering me to get her an electric violin, I decided to improvise one for her. I have been doing some research on the internet about Piezoelectric transducers. These are usually found in cheap $2 buzzers found readily at Sim Lim Tower. The surprising thing is that these buzzers can be used as pickups because the piezoelectric element will produce a signal when subjected to vibrations. So all it takes is a soldering iron and you got yourself a high quality pickup for your acoustic instrument.

Since it was so easy to make, I made one for my classical guitar and one for my daughter's violin. It worked better than I expected with good gain and negligible noise. I covered the piezo element with sticky foam pads meant as scratch protection pads for chairs.

When I showed my daughter the modification which I did to her violin, she was not very pleased and I realized that she might have some problems explaining all those black pieces of foam. I improved the placement and concealed it under the tailpiece. Now the only thing showing is a little pig tail. I told my daughter that if she happens to be on a stage where there are amplifiers around, she'd be able to plug in her violin and play directly.


Bob said...

Very interesting blog, thanks for all your work to share to the world you passions for bread, very delicious looking ware!

But I am more interested in the guitar/violin section. What kind of $2 buzzers are you referring to? If I lived near the Sim Lim Tower I would go there and find them, but since I live in Enderby, BC, Canada I have no idea where that is!! Please enlighten me if you get the chance, thanks, Bob.

tomsbread said...

HI Bob,

The piezoelectric buzzers look something like that

or something like that

I think they should be available in all electronic DIY stores. If not, rip one off an old unused PC. They are the ones generating the beeps. They can be found in some musical greeting cards too.

You can cut off the plastic casing with a cutter to extract the Piezo element from the buzzers.

This site from MIT was especially useful to me because I learnt that the pickup worked best when mounted as in a cantilever. That means only part of the disc is mounted with putty, leaving the rest of the disc free to vibrate. They did not work as well when I pasted it in full contact with the instrument body.

Good luck.

tomsbread said...

Can't believe I missed out the url for the MIT site

Bob said...

Thanks for all the info, now I get it! There are thousands of those buzzers around - thrift store are a haven. I'll get on it, you're a good man, Bob.

ixora said...

Would your daughter require another violin? I have a good quality full size student violin for sale, previous used by my daughter. Your creation on the buzzer was ingenious though I know nothing about it.

Incidentally, I love baking bread too. What do you mean by hydration? The amount of water added to flour?

tomsbread said...

Yes, you are right. Hydration refers to the amount of water added to the flour.

What type of violin are you selling? Are you in Singapore?

Anonymous said...

the useful information u presented do help our team's research for our group, thanks.

- Lucas