I have tried to drastically lower the pitch of a piezoelectric buzzer, but to no avail. All the piezo buzzers I have emit a very high pitched whistle-like tone. I've tried changing all the parameters of my pulse generator, i.e., frequency, duty width, spacing, amplitude, etc. but the pitch of the tone remains the same, very high! Is it even possible to make a base tone from a piezo, or is the high pitch an intrinsic characteristic of all piezo units?
The piezo I have is just a plain transducer, no internal circuitry. That's why I am using a pulse generator. What I am trying to do is move as much air as possible with a vibrating membrane unit that is extremely light and simple, which rules out heavy magnet/cone speakers of any size. I figure that a low bass sound would be the key. If not with piezo buzzers, what else could I try?
Best Answer
A piezoelectric buzzer has a built-in oscillator that will make a fixed frequency sound when you apply power - you can pulse that sound by turning the power off and on, but you can't change the frequency.
There are also piezoelectric transducers, where you can drive the thing with an audio frequency and it will produce that frequency sound. With these, you can change the frequency to some extent by changing the driving frequency - but i think most transducers will work best over a fairly narrow range of frequencies.