waverp – An Arduino Library for recording and playing wave files on the Adafruit Wave Shield

Preamp Shield

Nice! waverp – An Arduino Library for recording and playing wave files on the Adafruit Wave Shield.

WaveRP is an Arduino library for recording and playing Wave files with the Adafruit Wave Shield. It records 8-bit mono files at 4,000 to 44,100 samples per second. Use of the Wave record/play library, WaveRP, requires the following: Arduino with a 5 volt 328 processor. Low noise power source such as a nine volt DC adapter or battery. Adafruit Wave Shield (version 1.1 is best but 1.0 works) Microphone preamp. A circuit for a simple preamp is included in the documentation. Microphone, PC type with 3.5 mm plug. See the documentation for details. SD/SDHC formatted with 32KB allocation units.

Waveshield Med

The Wave Shield!
Adding quality audio to an electronic project is surprisingly difficult. Here is a shield for Arduinos that solves this problem. It can play up to 22KHz, 12bit uncompressed audio files of any length. It’s low cost, available as an easy-to-make kit. It has an onboard DAC, filter and op-amp for high quality output. Audio files are read off of an SD/MMC card, which are available at nearly any store. Volume can be controlled with the onboard thumbwheel potentiometer.

This shield is a kit, and comes with all parts you need to build it. Arduino, SD card, tools, speaker and headphones are not included. It is fairly easy to construct andanyone with a successful soldering project under their belt should be able to build it.

The shield comes with an Arduino library for easy use; simply drag uncompressed wave files onto the SD card and plug it in. Then use the library to play audio when buttons are pressed, or when a sensor goes off, or when serial data is received, etc. Audio is played asynchronously as an interrupt, so the Arduino can perform tasks while the audio is playing.

  • Can play any uncompressed 22KHz, 16bit, mono Wave (.wav) files of any size. While it isnt CD quality, it is certainly good enough to play music, have spoken word, or audio effects. Check out the demo video/audio at the webpage
  • Output is mono, into L and R channels, standard 3.5mm headphone jack and a connection for a speaker that is switched on when the headphones are unplugged
  • Files are read off of a FAT16-formatted SD/MMC card
  • Included library and examples makes playing audio easy
  • Please note that the library rather bulky, requiring 10K of flash and more than 1/2 K of RAM for buffering audio. It works fine using an ATmega168-based Arduino (or compatible) but for more complex projects I strongly recommend upgrading to an ATmega328!

More information, including design notes, schematics, library, examples, etc is at the Wave Shield webpage

Make a robot friend with Adafruit’s CRICKIT – A Creative Robotics & Interactive Construction Kit. It’s an add-on to our popular Circuit Playground Express, FEATHER and other platforms to make and program robots with CircuitPython, MakeCode, and Arduino. Start controlling motors, servos, solenoids. You also get signal pins, capacitive touch sensors, a NeoPixel driver and amplified speaker output. It complements & extends your boards so you can still use all the goodies on the microcontroller, now you have a robotics playground as well.

Join 7,500+ makers on Adafruit’s Discord channels and be part of the community! http://adafru.it/discord

CircuitPython in 2018 – Python on Microcontrollers is here!

Have an amazing project to share? Join the SHOW-AND-TELL every Wednesday night at 7:30pm ET on Google+ Hangouts.

Join us every Wednesday night at 8pm ET for Ask an Engineer!

Follow Adafruit on Instagram for top secret new products, behinds the scenes and more https://www.instagram.com/adafruit/

Maker Business — Fewer startups, and other collateral damage from the 2018 tariffs

Wearables — Light as a Worbla feather

Electronics — How to make your own magnetic field probe!

Biohacking — The State of DNA Analysis in Three Mindmaps

Python for Microcontrollers — One year of CircuitPython weeklies!

Get the only spam-free daily newsletter about wearables, running a "maker business", electronic tips and more! Subscribe at AdafruitDaily.com !


  1. So what is the daughtercard on the WaveShield in the first picture, and is it available for sale / general use? The picture name would imply that it’s a preamp(?)

  2. the schematic is in the file. there are no plans to sell a kit at this time but if you ask the fellow on the forums perhaps hed be willing to sell you one

  3. Hello

    The new WaveRP library is great.
    But is the playback still limited to 22KHz, 16-bit, mono ?
    Even if I can record @ 44.1KHz, 8-bit.
    What is the maximum output quality I can get?

  4. hi!

    it’s not clear what’s included in the kit from your online store.

    can it be used with an external dac chip? can i tap i2s (or some dac format data) from the controller?



  5. Hi,
    Wondering if it is possible to transfer the audio files stored on the SD card into a connected PC via USB.


Sorry, the comment form is closed at this time.