After hearing the song Piezo by Autechre several years ago, I really liked the word. But I never really knew what it was until yesterday when my friend told me it is a thingamagig that sits behind the tweeter in a speaker. Does anyone here know if Axiom's tweeters use a piezo, and if so, what advantages it has?

thanks!

Hi Ravi,

In reference to speaker drivers (usually tweeters), the term is generally "piezoelectric". It's an element or crystal, sometimes combined with ceramic, that bends or moves in response to an applied voltage. About 15 or 20 years ago, piezoelectric tweeters had a brief period of popularity and showed up in a few speaker designs. In my experience, piezo tweeters had a very ragged response pattern, with resulting harsh sound. They're seldom used nowadays. If I recall, piezo tweeters were extremely sensitive, able to produce very loud sound with very few watts input.

Regards,

Are you sure the song wasn't "Pie Jesu" by Andrew Lloyd Weber?

..."ain't I a stinker?"

--Bugs Bunny

If I remember my electronics from several years ago, the term is derived from piezoelectric effect, which describes the phenomenon of a crystal oscillating when an electric voltage is applied to it. The frequency of the oscillation is a function of the geometry and composition of the crystal. Most electronic (and almost all digital) circuits use these arrangements to generate a timebase (clock) signal in view of their stability.

This same principle has been utilized in making tweeters which did not possess much of a frequency range or power output but lent themselves easily to miniaturization (as there is no coil/diaphragm involved) and therefore have become commonplace in alarm clocks, beepers and the like.