High power ultrasonic transducer?

[cds333]

I am trying to find a supplier of ultrasonic transducers, that are both high power, work in the air, and meant to work with variable frequency.

So far I can only find ONE place that sells them, and he goes out of his way to remove any manufacturer info, so I have no tech specs whatsoever (besides a random dB or wattage claim)

Whenever I search for "ultrasonic air transducer" all I get are these tiny piezo elements the size of a nickel, that are definitely not high power.

If I search "high power ultrasonic transducer" I get the kind meant to go in an ultrasonic parts cleaner, which only list a single frequency (and I assume are not meant to attach a horn to for using in the air).

The kind I am looking for are like these:

https://www.amazing1.com/products/phasor-pain-field-generator-rc-high-power-4-transducers-focus-tubes.html
https://myskunkworks.net/index.php?route=product/product&path=61&product_id=61
https://myskunkworks.net/index.php?route=product/product&path=61&product_id=84

So I can build a device capable of broadcasting audible through ultrasonic frequency sound through a horn.

Why am I having so much trouble finding these???

Any help would be very much appreciated.

[Kim Christensen]

Those tiny piezo elements have a very narrow frequency range as do the ultrasonic parts cleaner transducers. That's why they list the resonant and anti-resonant frequencies.
You may be able to find a "horn tweeter" that goes high enough. (The 3rd one you listed looks like a tweeter) What's the frequency range required?

[strawberry]

https://www.ebay.ie/itm/100W-28KHz-Silvery-Aluminum-Alloy-Ultrasonic-Piezoelectric-Transducer-Cleaner-/322142080595
add horn
tune each transducer for specific range
frequency range could be limited by mechanical resonance

[TurboTom]

The piezo air transduces form your links appear ridiculously overpriced. They are just acoustic piezo horn drivers. See here: https://www.pollin.de/p/piezo-hochtontreiber-mcgee-hlq-02-80-w-641370

Unfortunately, this is a link to a german reseller but I'm sure you'll find similar offers in any country. Just search for "Piezo Tweeter".

"Real" high-power ultrasonic transducers are resonant devices that won't provide much conversion efficiency far off their natural frequency.

[cds333]

@Kim Christensen

Lets say 3kHz-30kHz

@strawberry

Are you saying it is possible to tune that transducer you listed? If so- how would one accomplish this?

@TurboTom

LOL yeah I expected something like that. It is a 400% markup, now that I know what it is called and can find it. Thank you!

[Kim Christensen]

Lets say 3kHz-30kHz

Here is one that specs it as 1.8Khz to 30Khz, though it's response plot only shows up to 20khz. So it's hard to say exactly how well it works above 20Khz.
I'm sure if you Google around you should be able to find something that'll work.

[cds333]

Actually I would not mind spending more for something better (all those ~$10 piezo driver types seem to have unfavorable reviews on Amazon)

As I am not an expert on speaker construction, I do not know the subtle differences between the performance of the "piezo horn driver", for example, and a "neodymium bullet super tweeter"

I do not care about sound quality, as it will not be used for music. I am mainly concerned with build quality and loudness. (I don't care if a note is a few Hz off.) I realize the more expensive ones that are marketed for music will usually not go past audible range.

Also I notice that most of the Goldwood ones that claim to go to ~30kHz include a chart that stops at 20kHz. I find that a little suspicious. Almost as if they realize the human ear will never know the difference...

Then there's this one that claims to go to 40kHz!

[strawberry]

Then there's this one that claims to go to 40kHz!

impedance graph show maximum 40kHz at max 4Wrms ,at 45kHz impedance could be below 1ohm
max frequency depend on ceramic capacitance
can use two transducers for different range