A Bike-Friendly, DIY Action Cam Stereo Microphone

November 7, 2026 by Donald Papp 1 Comment

[DJJules] had two problems. Being an avid biker, recording audio on a bike-mounted action camera was less than ideal due to wind. In addition, the built-in microphone on action cameras is also just not as good as a dedicated stereo microphone setup. His solution: The Bike Mike.

The furry ends contain one mic each, mounted with foam.

The Bike Mike solves both problems at once by providing a windproof stereo microphone for [DJJules]’s bike-mounted action camera. It consists of a 3D printed frame and mount for two electret microphones. The mics each get a foam cover, and are surrounded by a cage upon which furry mic covers are applied.

The microphones are wired up to a 3.5 mm audio connector, which is a pretty straightforward soldering job. To make it compatible with the action camera, [DJJules] uses a super slim USB microphone adapter that accepts the 3.5 mm connector on one end, and provides a USB-C plug on the other. One can insert that directly into the camera and have it recognized as an external mic.

If this looks a bit familiar, it’s similar to his earlier design for a DIY external stereo mic for things like DSLR cameras. This one’s adapted for action cameras, integrating a USB adapter for a wider compatibility.

Embedded is a build video followed by sample footage, so give it a watch and listen for yourself.

Continue reading “A Bike-Friendly, DIY Action Cam Stereo Microphone” →

Track Bird Visitors With A Raspberry Pi And A USB Mic

August 8, 2026 by Donald Papp 22 Comments

Avian Visitors is a lovely project by [Teddy Warner] that uses a Raspberry Pi and microphone to keep track of which birds have been visiting your home, and creates a colorful illustration of recent visitors on top of it all.

It reports on a web interface of its own making, but what really takes things to a new level is an optional, stylish E-Ink panel that shows the last 24 hours’ worth of visitors at a glance in a collage.

The key to identification is BirdNET (GitHub here), a deep learning classifier from Cornell that can reliably identify and classify more than 11,000 species worldwide based on sound alone.

Based on that information, the system pulls bird images from a reference set for the region and creates a collage representing the breadth and frequency of visitors in a single image. The larger the image of a bird, the more frequently it was heard.

That’s a cool project, but [Teddy] took things one step further by setting up a color E-Ink display to show a running summary of all the avian visitors the system identifies. [Teddy] has a knack for leveraging projects into wall-mounted art, as we saw with his generative art wall plotter. Continue reading “Track Bird Visitors With A Raspberry Pi And A USB Mic” →

Mico Is A USB Microphone Based On A Pi Pico

December 25, 2021 by Robin Kearey 20 Comments

When [Mahesh Venkitachalam] was experimenting with machine learning for audio applications on a Raspberry Pi, he found himself looking for a simple USB microphone. A cheap one was easy to find, but the sound quality and directionality left much to be desired. A large, studio-quality mic would be overkill, so [Mahesh] decided to simply build exactly what was needed: a compact, yet high-quality USB microphone that he called Mico.

The sensing device is a MEMS microphone that outputs a pulse density modulated (PDM) signal. There are chips available to directly interface such a microphone to a USB port, but [Mahesh] found them difficult to work with and therefore settled on something he knew already: the Raspberry Pi Pico platform. Luckily, someone had already figured out how to read out a microphone and present a USB device to a PC, so all that was needed was to put all the bits together into a convenient form factor.

The great thing about the Pico platform is that its main controller chip, the RP2040, is available as a separate component. [Mahesh] designed a sleek little PCB that holds the RP2040 along with the MEMS microphone and a USB connector. The end result looks tidy enough that it might have come out of a mass-produced gizmo. Those don’t usually come with full schematics and source code, but the Mico does: everything is available on its GitHub page for anyone to re-use and improve.

You can judge the sound quality for yourself in the video embedded below. If you like DIY USB microphones, you’re in luck: we’ve featured one based on an STM32 as well as a beautiful recreation of a studio-quality mic.

Continue reading “Mico Is A USB Microphone Based On A Pi Pico” →