DSP filter designing

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Wicky21

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First of all i want to say i'm not much familiar with DSP filter designing. But i'm currently doing a project to identify mosquito detection. In my case i already know mosquito frequency ranges.
Fundamental frequency = 350Hz - 500Hz
1st,2nd harmonic around = 700Hz-1400Hz
3rd harmonic = 1500Hz-1900Hz

I want to pick signals from 350Hz - 1900Hz. My application was a real time device. It will capture frequencies from a microphone. Also it has lot of noise. In my case i want to make a dsp filter which can cancel out other frequencies. One of my Senior lecturer suggested me to make IIR bandpass filter on the micro-controller also calculate coefficient from MATLAB fdatool.
Since i'm using teensy 3.2 on my project guys please guide me. Also i have seen when designing biquad filter which has corner frequency below 400Hz, filter performance is poor.
Guys please help me on my project
 
Yes. I'm going to use Teensy fft library some how. Since this device need to be fully automated after filtering it will calculate fft.
Paul please guide me
 
On the matter of implementing filters, have you actually used your Teensy yet with the audio lib? Have you gone through the tutorial? It has a section about using filters. Admittedly the tutorial covers only the simplest filter type, but it definitely the place to start to gain a little practical experience. Even if that material doesn't directly apply, it'll give you a much better background and confidence to do this project. And it's easy, since the tutorial is already written and the code is already in the File > Examples > Audio > Tutorial menu, and on top of all that we made a full walkthrough video so you can see and hear every step in case you get stuck.
 
I have ordered teensy. But still i didn't got the boards yet. Mean time im going through every steps and clarify my doubts. Then after receiving boards without no time i can start. Also paul i'm not using audio shield. instead i thought to use MAX9814 microphone. Also i have gone through with the tutorials.
 
First things first, get the mic and a headphone amp connected to the Teensy and get them working with the passthrough example.

Headphones, not speakers, are essential for testing with a mic, so you can hear what's happening without the sound getting back into the mic.

This is much easier with the audio shield, but you can also do it by building the recommended ADC input circuit and also building a headphone amp so you can listen to the DAC output. Do this first.
 
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