When I was working on my time-lapse camera badge hack for last year's 2017 Superconference badge, I had the luck to meet Ben a.k.a Electromage, creator of Pixelblaze. He was sitting across the table from me and had to stare at the backside of my Luggable PC Mark II for most of the weekend. Our paths crossed again earlier in 2018 at the Bay Area Maker Faire, where I was working for Tindie's booth and he stopped by to drop off a sample Pixelblaze unit as he sells on Tindie. After my booth shift was over, I stopped by his booth set up to promote Pixelblaze and was impressed by what I saw.

I don't recall anything demonstrating Pixelblaze at Supercon 2017, but Ben brought a nice attention-pulling demo for Supercon 2018: a sound-reactive LED cube controlled by Pixelblaze with optional sensor expansion board. It was sitting in front of him on the badge hacking bench as he worked most of the weekend on that ESP32 mesh network. Here's a view of the cube looking down the length of the bench at all the other badge hackers.

Pixelblaze Cube

The cube's five visible sides each had an 8x8 = 64 LED array, and they react to changes in sound volume. The microphone is part of the sensor expansion board and is paired with its own processor to dynamically adjust to local ambient noise level to pick out sharp changes. All that audio processing was required, Ben explained, because electronic microphones don't react to sound the same way human hearing does. His algorithms make the sensor board act similarly to how a human being perceive sound. All this is necessary so a Pixelblaze program reacting to sound would "look right" to a human observer.

After seeing Pixelblaze in action at Bay Area Maker Faire, I added "play with Pixelblaze" to my electronic to-do list. Seeing this sound-reactive demo cube in action at Supercon 2018 promoted it higher on my list. And now, thanks to an unexpected series of events and Ben's generosity, I now have one on hand I could play with.

My first challenge: I don't have an individually-addressable LED strip/array to use with this Pixelblaze. Reading Pixelblaze documentation I learn the APA-102 series of LED modules are the best match for Pixelblaze capabilities, so I've ordered a meter long strip to start. I'm looking forward to seeing what I can do with it.

https://twitter.com/hackaday/status/1058846639547281410