AudioMoth Dev is a full-spectrum acoustic development board based on SiLabs EFM32 MCU

AudioMoth is a low-cost, open-source acoustic monitoring device that can record uncompressed audio from 8000 up to 384,000 samples per second onto a microSD card. With sensitivity to audible sounds as well as ultrasonic frequency range, It is mostly used for monitoring wildlife including bats, cicadas, the rainforest, etc…

The manufacturer, Open Acoustic Devices, is now offering the development board version with AudioMoth Dev, based on a Silicon Labs EFM32 Wonder Gecko MCU like the full device, for $79.99 + shipping on GrougGets.

AudioMoth Dev board specifications:

Wireless microcontroller – Silicon Labs EFM32 Wonder Gecko Cortex-M4F MCU @ 48MHz with 256kB Flash, 32kB RAM
External RAM – 256kB SRAM
Storage – MicroSD card slot
Audio capture
- On-board analog MEMS microphone, sensitivity -38 dBV/Pa, 63 dBA SNR, 10Hz to 192kHz
- Sample rates up to 384kHz
- 3.5 mm jack socket for external electret condenser microphones (Note: the optional case not compatible when using an external mic)
USB – Micro USB B port for power, configuration, and for reprogramming the flash
Expansion
- 4-pin header for multi-function 3V General Purpose I/O (GPIO)
- 3-pin header for external red and green LED’s
- 3-pin header for an external switch
Debugging – 6-pin serial wire debug port
Power Supply
- 2-pin header for external power supplies/batteries (3.3V to 6V)
- 2-pin header for powering external 3V boards or products from AudioMoth Dev

AudioMoth Dev is compatible with AudioMoth version 1.2.0 acoustic monitoring device ($84.00) that comes with a holder for three AA batteries, and an optional IPX7 waterproof enclosure. That means you can see the same instructions for the board as for the device, and the main benefit is access to power signals and IOs via JST headers. The board can be configured from a computer or laptop running Windows, Linux, or Mac OS, as well as Android or iOS mobile devices.

The AudioMoth Configuration app lets you set schedules, audio settings like sample rate, gain, or duration, as well as advanced settings to filter frequencies or only record within an amplitude range, among other parameters.

If you’d rather not make your own case, which could be a zipped bag, the official AudioMoth IPX7 waterproof case is also offered on GroupGets for $34.99. It is designed to handle up to one-meter submersion for one hour with no leakage, comes with a Velcro strap for easy deployment on 3-6 cm diameter branches/poles, and a clasp for simple battery and MicroSD card changes.

Jean-Luc Aufranc (CNXSoft)

Jean-Luc started CNX Software in 2010 as a part-time endeavor, before quitting his job as a software engineering manager, and starting to write daily news, and reviews full time later in 2011.