Arduino Audio Samples

Hello Makers,

It has been awhile and I have missed you :) Lets get back into it and do audio samples!

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Amanda Ghassaei (http://www.amandaghassaei.com/images/arduinodsp/output3.jpg)

Including sound in a project makes anything cooler but the Arduino has pretty severe limitation when it comes to audio. The Tone library (https://www.arduino.cc/en/Reference/Tone) is simple but it can only play one tone at a time. Then the internal memory space (https://www.arduino.cc/en/Tutorial/Memory) in an Arduino Uno is limited to 32k which is less then a second of sound and that is only if you have no code :) Finally there is no true DAC (https://www.arduino.cc/en/Reference/AnalogWrite) on the Uno. Most code uses PWM (https://www.arduino.cc/en/Tutorial/PWM) to produce an "analog signal" but if you run that through a speaker you hear some pretty nasty harmonics.

What I want to demo do is a simple system for getting clear sounding audio samples. To do this we will combine a standard SD card

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Adafruit (https://www.adafruit.com/product/254)

with the WAV playing TMRpcm (https://github.com/TMRh20/TMRpcm) library and a R-2R DAC (http://hackaday.com/2015/11/05/logic-noise-digital-to-analog-with-an-r-2r-dac/)interface.

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Makezine (https://i0.wp.com/cdn.makezine.com/uploads/2011/02/r2rdac-v2.gif?w=600)

and we will see if it all works together :) This project provides a lot of flexibility for audio projects plus it shows how to add a easy DAC to any Arduino project. Also the R-2R DAC is a nice demonstration of the trade off between circuit simplicity and I/O usage.

The demo will take the first half an hour. Then there will be open project time to work on any project you want. You can work on one the previous projects (https://github.com/theengineeraccelerator/Beyond-Hello-World) or bring your own.

See you there!

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Thanks for coming to to Beyond Hello World Electronics! Please note that children under 14 need to be accompanied by an adult.

This project is part of The Engineer Accelerator (http://www.engineeraccelerator.com/) - The place for hardware engineer to complete their professional skill set.