One of the great things about Atmel’s ATMEGA328P microcontroller that powers the Arduino Uno boards is the sheer versatility of the chip. It might only clock in at 16MHz and process data in 8-bit chunks, but it has so many practical real-world interface options that helps it punch well above its weight.
My favourite part of the chip is the ADC or ‘analog to digital converter’. By rights, it’s only a 10-bit ADC and only has a rated sample rate of around 9.6kHz, but with a little ‘code karate’, you can push that sample rate beyond 70kHz and still maintain 8-bit accuracy.
Perform a few other tricks and you can lock that sample rate to pretty darn close to 44.1kHz. Add in some extra coding to create a WAV file header and the Arduino Uno all of a sudden becomes a more-than-passable digital audio recorder.
Earlier this year, I wrote a two-part feature on how to do just that, including all the how-to stuff – circuit diagram, parts and the software or ‘sketch’ that makes it work.
I don’t expect it will worry the likes of Marantz or Tascam, but if you want to learn how digital audio recording works by actually building your own, this would be a great place to start. Enjoy.