Acusis, an Echo-Cancelling Far-Field Microphone Array
Over the last few years voice computer interfaces have become much more powerful, and while there are some security concerns, that hasn’t stopped counter top home assistants—such as Amazon’s Alexa or the Google Home—becoming relatively common.
That’s led to a confusingly large amount of third-party hardware, software, and tutorials on how to build your own voice assistant. In the course of a just year or two its gone from impossibly hard, to simple, to build your own.
One thing that’s driven this trend is the availability of far-field microphone arrays, and we’ve seen a number of them in recent months ranging from cheap to rather more expensive—they’ve even been given away on the covers of magazines. Until recently however most of these haven’t done echo-cancellation, and while there are boards that do, they’re not always available off the shelf. Which makes the Acusis board, currently raising on Crowd Supply, rather interesting.
The Acusis is an echo-canceling, far-field, microphone array. Unlike a lot of boards it doesn’t imitate the Alexa’s circular shape, the Acusis is a linear array designed to be mounted on top of a monitor, or to the front of a web camera.
When connected to your computer via USB the board will show up both as a microphone and a speaker, since to remove echos from your microphone input the board needs to receive the audio you are producing. The board can either be configured to “pass through” audio to your real speakers, or as a secondary device — on a Mac for instance this can be done using the Audio MIDI Setup application.
The Acusis is built around the XMOS XVF3000 voice processor, a single chip solution that supports up to four PDM microphones, USB and audio output, as well as on-board DSPs for beamforming and echo cancellation.
While the Acusis is usable out-the-box that means that it’s also hackable. You can download the SDK from XMOS and, along with the necessary XTAG programmer, write your own code.
The Acusis board is currently raising on CrowdSupply, with just over 40 days left to run the campaign has raised around a third of it’s $6,300 target. An assembled Acusis board is priced at $69 with free shipping inside the United States, and an extra $15 for shipping for the rest of the world.