Canyonero wrote:
Hi out there in Usenet electronics land.

Was hoping to get a little help on something that should be pretty
simple.

I want to vibrate a metal plate at different frequencies using a piezo
buzzer or transducer of some type for some Cymatic experiments.

I can use the output from a computer or stereo to generate lots of
tones but how do I drive a piezo element with a speaker output ?

This question is probably embarassingly easy to answer but I have
never used a piezo element for anything other than creating a spark to
light my cigarettes.

Thank you in advance.

You may be looking for a "tactile transducer".
There are different sizes available for many
different purposes, here are a few links to
get you started on your search.

http://www.baudline.com/erik/bass/tactile_faq.html

http://www.smarthome.com/8248.html

Large high power units are expensive but I've seen
designs for home made transducers in the past.

[8~{} Uncle Monster