Piezo Transducers

[sbonasuk]

Under the assumption that if something costs more it should therefore be better, I went searching through the Farnell catalogue looking for the best piezo I could find. The original transducers I bought from eBay were essentially pennies and therefore prone to a vast range or variance. The type of piezo I have had the most success with on my Cymbals were plastic housed and I think about 30 35mm.

However looking through the specs there are apart from size, three specs voltage, frequency and sound level. Can anyone tell me what the optimum specifications that suits MD the best

Thank you

[dmitri]

From my experience, the signal quality mostly depends on the build design/quality of a pad/cymbal rather then the specs of a piezo. I think any 20-40mm piezos will do regardless of their voltage, frequency or sound level.

[privatex]

The type of piezo I have had the most success with on my Cymbals were plastic housed and I think about 30 35mm.

My snare piezo head sensor have something similar, I glued aluminium ring on bottom side of piezo (coincides with edge of piezo) and on top of sensor are cone ofc, that gives me way better results because piezo have more space for vibrating. That is the essence of your conclusion.
Way how you put piezo and other mechanical parts is crucial.

[sbonasuk]

Any chance of a picture of that construction, I was considering doing the same thing especially with the snare which takes the most beating

thanks

[privatex]

I can't make pics sorry, it's a ring about 35mm, 2mm hight glued on metal side of piezo and than together glued to some bronze plate + foam for isolation. On ceramic part of piezo goes foam cone and that's it. If your pad is 'cold' this is one way to make it more sensitive.
You can use plastic, metal, foam... whatever ring, piezo need to have free area for vibrating (with different materials you can get slightly different results, experiment and you will find your best setup). That piezos in plastic housing is used as buzzer.

[sbonasuk]

I took your advice, by chance I had bought a job lot of piezo's on eBay there large units with a ring mounting superbly they turned out to be high quality murata around £5.00 each. However having used all them I had an 8" Tom left to do so found a circular piece of plastic, mounted the piezo so there is a 1 to 2mm gap, double sided foam tape to the aluminium bracket and double sided tape to the ceramic side for the foam cone. Works perfectly consistent output. I have taken pictures of the build of my snare when I rebuilt it with the new piezo's, as soon as I can remember how to post images to a web site I'll put them on the forum.

[privatex]

Good news! My snare pad only work with that ring, otherwise it's too 'cold'.

[stefan1982]

Is there any link to these piezo's you guys talk about?
I'm curious...

[privatex]

They are not some special piezos. Take regular disc piezo and glue plastic,aluminium or whatever ring on flat metal side (I use alu ring which have a little shorter diameter than brass disc). That way piezo have more area to freely vibrate. Here are some pics:



I changed the size of cone too, it gives same results as bigger one.

[sbonasuk]

These are the images of my snare rebuild,



Privatex is right of course, the expensive piezos are not necessary It was just a coincidence that the job lot I bought happened to have some high cost units, however my 8" tom is made just like the one in the Privatex pictures using a plastic ring, the point here is that it having a gap to allow the piezo to vibrate, and the high density foam makes a good setup.