Hi,
I have a question regarding perform FFT on an analogpin pin on Teensy3.0 without using the Audio Shield.
In the Audio System Design Tool, when using the acd1 block, in the info section, there is a recommended circuitry to use. May I know the purpose of this circuitry. Can't I just connect a microphone breakout board (http://www.adafruit.com/product/1063) directly to the teensy (Gnd, 3.3V and A2). Is it because the default signal range used by the audio library is 0 to 1.2V? So the circuit is used to bias the microphone signal output to fluctuate between 0 to 1.2? In that case is it possible to change this signal range to 0 to 3.3V instead so that I can do away with those additional resistors and capacitors in the microphone circuit.
Another question... I just want to perform a 1024 point FFT on a signal picked up by an external eletrect microphone. What advantage is there to use the audio shield as compared to just connecting the microphone directly to the analoginput pin on the teensy? I am looking at a sampling rate of 44100 Hz. If I were to use the audio shield, should I connect the microphone to the mic input or to the line in input? The microphone breakout board from Adafruit already has the biasing circuit.
Cheers,
Kian
I have a question regarding perform FFT on an analogpin pin on Teensy3.0 without using the Audio Shield.
In the Audio System Design Tool, when using the acd1 block, in the info section, there is a recommended circuitry to use. May I know the purpose of this circuitry. Can't I just connect a microphone breakout board (http://www.adafruit.com/product/1063) directly to the teensy (Gnd, 3.3V and A2). Is it because the default signal range used by the audio library is 0 to 1.2V? So the circuit is used to bias the microphone signal output to fluctuate between 0 to 1.2? In that case is it possible to change this signal range to 0 to 3.3V instead so that I can do away with those additional resistors and capacitors in the microphone circuit.
Another question... I just want to perform a 1024 point FFT on a signal picked up by an external eletrect microphone. What advantage is there to use the audio shield as compared to just connecting the microphone directly to the analoginput pin on the teensy? I am looking at a sampling rate of 44100 Hz. If I were to use the audio shield, should I connect the microphone to the mic input or to the line in input? The microphone breakout board from Adafruit already has the biasing circuit.
Cheers,
Kian