Natural Science Forum / Physics / Acoustics / September 2005

I "may" be able to provide you with more relevant information but I would
need to know the details of your specific application.

Sorry I couldn't be more helpful. But there isn't much of a
market it seems for acoustic transducers higher than
say 20 kHz.

There are some transducers you can find around that are
made for specific frequencies such as 22 kHz, 25 kHz,
and 40 kHz that are used primarily in ultrasonic alarm systems where one
transducer sends out an ultrasonic wave while another transducer receives it and
uses it to determine
if anybody is in a room.

Most transducers are used in water for sonar, ultrasonic cleaning, non-destructive
testing, and other experimental
purposes. Underwater transducers can operate well up
into the MHz range and beyond. But to get anything higher than 50 kHz in air your
choices are severely limited to
ultrasonic whistles and sirens-- but requiring compressed
air to get them to work.

There are a lot of patents in the US Patent Office that
show how to make a transducer; if you don't have
need for a lot of acoustic power, you could probably
make your own transducer if you go to the trouble of purchasing piezo-ceramic
disks or bimorphs, electrically conductive glue, and assorted metal items. While
this is a true pain in the a.s, it may be the only way to get what you want if you
really need it badly enough. Although maybe one of the piezo companies might make
a custom transducer if you are willing to pay an arm and a leg for it.  ;-)

Best wishes,
Ron