quad or more mono channel analog audio

Status
Not open for further replies.
The internal ADCs, although documented having 16bit, have only a usable resolution of 12bit in single ended mode and 13bit in differential mode. The rest is noise. Thus, I'd strongly recommend the audio board.
 
Indeed the audio shield inputs are much better than the pins on the microcontroller.

You might also check your microphone specs, plus whatever amplifier you'll use (no mics give a signal large enough for direct ADC input). Many of the cheap electret mics have about 60 dB signal to noise ratio. And those specs are quite charitable, tested with the loudest sounds. If your sound isn't at loud as the maximum used for testing, in practice you'll end up with lower signal to noise than the spec tested with an extremely loud sound.

Really good mics tend to have a self noise rating, specified in actual sound pressure level. So if you have a loud 90 dB SPL sound and you use a 20 dB self noise mic, you'll end up with 70 dB signal to noise ratio.

A simple rule-of-thumb is each 6 dB signal-to-noise is approx 1 bit.
 
Thanks Paul for the tip, and yeah i've brought one with a preamp so il just use that to test it out then move on to making my own amp/ buying a better microphone capsule at a later point.
 
Status
Not open for further replies.
Back
Top