Kyu Tae Yoo wrote:

> Hello,
>
> I am trying to measure the frequency response of a capacitive
> micromachined microphone. I am using a super tweeter as a sound
> source upto 40KHz, but I am also interested in the frequency response
> beyond the audio frequency ( possibly upto 150 KHz). Does anyone know
> which transducers are capable of generating low ultrasound (40~150KHz)?
> and Who makes them?
> Thank you, and have a wonderful day
>
>

There are few manufacturers of ultrasonic transducers working in air. It is
relatively easy possible
to get transducers working in the frequency range up to 400KHz. But they are
narrowband.

In America you can for example find Airmar - this corporation is producing
transducers working till
300kHz.


Wieslaw Bicz

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