how do i filter out all other unwanted sound except for hand clapping sound?

hi all! i'm doing a sound recognition desktop fan. I'm using hand clapping to trigger its speed. So i need to filter out all other unwanted sound except for hand clapping sound. I have tried to design a 2.2k-2.8khz bandpass filter to filter that, but it did not work. Is it my frequency range problem or my circuit design problem? Coz i'm also not sure about the hand clapping sound frequency range and my designated resistors and capacitors values since i took the frequency range from a site and the passband gain i just simply assume it is 2. Please give me so advice ty :-(

I don't know if I'm totally wrong about this but I've always assumed
handclap detectors just used some simple sort of "spike" detection.

You'd just need to look for a short rise time followed by short fall time
with sufficient amplitude. Or maybe just something even simpler
to switch on saturation. A schmitt trigger or something perhaps.

Unless you have a specific need perhaps bandpassing would be a bit of overkill?

jack

As 123jack said, you would want to look at a spike in volume in the audible spectrum. The problem with hand clapping is that it's not very uniform. Depending on how tight the skin is, what part of the hand is being hit, or how the the hands come together can all change the tone of the clap. The hand will not produce just one frequency, but a collection of many frequencies. If external noise is the big concern, though, you could always check the "tuning" of your hand to find out the pitch of the principle harmonic. Try looking up a free online pitch pipe, if you don't mind looking silly clapping at your computer. Unfortunately, the fan itself may be noisy enough to produce a wide range of frequencies as well. Looking at the magnitude of the volume would probably be the best way to go. I personally would try just filtering for the audio spectrum, amplifying, and then using a comparator set against a reference threshold.