This is the Teensy 4 Audio Shield (Rev D) that can be added to a Teensy 4.0 for your next audio project. The shield provides you with an easy-to-use tool to add high quality 16 bit, 44.1 kHz sample rate audio to your Teensy. With the audio library provided in the Documents tab, you will be able to use both the input and output simultaneously in order to make a variety of great audio projects, incorporate synth waveforms, effects, and mix multiple sound streams and CD quality audio to your headphones or different line outs! The Teensy Audio shield utilizes the SGTL5000 stereo codec with headphone amp IC to decode and drive audio files and the Cortex-M4 DSP instructions from the Teensy dev board to provide power to a real-time FFT. Each board is also equipped with 3.5mm audio jack for headphones, a micro-SD card slot for storing audio files, and optional spaces for a 25k potentiometer (volume control) and flash memory chip. The two rows of 14x1 headers are not included to give you the freedom to choose how to connect your audio board with your Teensy. **Note:** Please be aware that a Teensy 4.0 will also need to be purchased to get your Teensy Audio Shield operational. **Features:** * 16 bit, 44.1kHz Sample Rate Audio * Plays Uncompressed WAV and Raw Audio Files * 4 Channel Software Mixer * 3.5mm Audio Jack * micro-SD Card Slot * Supports Stereo Headphone and Stereo Line-Level Output **Documents:** * [Datasheet](http://cdn.sparkfun.com/datasheets/Dev/Teensy/SGTL5000.pdf) (SGTL5000) * [Audio System Design Tool](http://www.pjrc.com/teensy/gui/) ([Example](https://cdn.sparkfun.com/datasheets/Dev/Teensy/audiotool.png)) * [Audio Library Wiki](http://www.pjrc.com/teensy/td_libs_Audio.html) * [Audio Library GitHub](https://github.com/PaulStoffregen/Audio)
