I used to build speakers for homes and Jeeps. There is a publication titled "Speaker Builder". The equations given fall into line with your query. Google it.
Just for reference a speaker is a tuned enclosure comprising one or more drivers - not the/a driver itself.
Hmmm!
From an embedded controls perspective....
You can use an ultrasonic transducer in a receive-only mode, yeah, a fancy microphone. How about quantification?
4-cylinder engine, overhead cam, up to 7K rpm ignoring aspiration method.
To determine what data we are looking for one would have...
