I'd like to know if there is a solution that allows me to measure the frequency of vibration of a surface/object. Primarily I am seeking to improve my speaker/home audio setup. The vibrometers I've found (and can afford) can give me the amplitude of vibration, speed of vibration and acceleration of vibration. I want to be able to measure what frequencies an object is vibrating at, though. If anyone could help me out, either by pointing me towards tools that can meet my needs, or letting me know how to derive the frequency from other data, I'll be grateful.
An easy and cheaper way to do this is with a microphone (basically an uncalibrated vibration sensor!) and an oscilloscope, upon which you display the microphone output. The frequency of vibration can be extracted from the oscilloscope display by measuring the time between peaks of the waveform; the inverse of that time is the frequency of the vibration.