Is is feasible to build an audio recorder with SD card storage using ATmega 16 or 32 running at say 16 MHz?
If yes, what would it need in components? I don't expect you to make a device for me, but a high level overview of needed parts would be welcome.
I'm thinking of using an electret microphone and use the integrated ADC to capture audio and then save the signal to a FAT formatted SD card in a popular sound format if possible but if needed I could make a custom format and convert the data once it reaches PC.
I know that I'd of course need a power supply, SD card reader, microphone, AVR itself, but would I need some sort of filter at microphone's input? I'm mostly targeting human speech and it appears that I need to mainly focus at frequencies from 60 Hz to 7 kHz. I also heard that most of useful data is below 3 kHz.
Also right now, I don't have the feel for amount of memory the device would need, so if ATmega 32 is overkill, which smaller AVR would fit? I hope to go for as low pin count as possible.