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6 of 6 boards

Sound

Short sounds and spoken keywords, from a microphone. Teach a board to hear a keyword, a clap, a door knock or the click of a switch, and to tell them from background noise.

Limits first

  • Short sounds and a handful of keywords, not speech recognition.
  • Your board needs a microphone. The Nano 33 BLE has one onboard; the other boards need a microphone module, and on some of them memory is tight (see the table).
  • The downloaded code runs the model on a buffer of audio your code fills.

Which boards can do it

Sound support on each board, from our board registry.
BoardSupportWhy
ESP32-S3-DevKitC-1 (N8R8) Supported
Arduino Nano 33 BLE Sense Rev2 Supported Onboard mic
Raspberry Pi Pico 2 W Limited Module + tight RAM
Nordic nRF52840 DK Limited Module
ST Nucleo-H753ZI Supported
ST Nucleo-F446RE Limited Module + 128 KB is tighter than nano33ble/nrf52840dk's 256 KB

How you collect it

Record with your phone's microphone, one sound at a time or in one continuous take that is split at the silences for you. Audio is recorded at 16 kHz.

What you need

  • At least 5 recordings of each sound, from at least 2 separate sessions, before the report will quote an accuracy.
  • A label for the background, recorded in the room the board will live in, so the model learns what to ignore.

Getting a good model

Record each sound in several separate sessions and at different distances from the microphone. Sounds are turned into MFCC features and classified by a small depthwise-separable network that is built to fit a microcontroller.

Start a sound project

Create a free account, open a project and add your first examples.

Other signals: MotionSensor values