There are only so many blinking light patterns you can create with a microcontroller before you get bored. [Garrett] apparently felt that way and decided to build a music-driven LED display on some LED shades. The system has three main elements: a microphone, a preamp, and a 7-band spectrum analyzer chip. You can see the results in the video below.
[Garrett’s] project spans three consecutive posts, and he includes quite a bit of design detail including a Javascript calculator and a spreadsheet. The spectrum analyzer chip, an MSGEQ7, is an inexpensive chip that reads an audio signal and outputs the signal strength for each of seven bands. The chip doesn’t have many pins, so it multiplexes the output to a single pin.
In addition to the hardware design, [Garrett] also shows his technique for building the project on a printed circuit board. He also has an interesting trick to hold down solder stencils with spray glue. We’ve been big fans of these glasses since we first saw [Garrett] with them at Maker Faire a few years back. We still have a few pairs in stock in the Hackaday Store.
We’ve seen these inexpensive spectrum analyzer chips used on bicycles. They’ve even been the butt of some light jokes (we’ll leave the inevitable Bud Light jokes to the commenters).
Wouldn’t one have cut a swath on the dancefloor with a pair of those in the days of disco!
The Future’s So Bright, I Gotta Wear Shades.
The future’s so shady, I gotta wear brights.
i almost spit out my drink
i almost drank out all the spit
Is it Garrett or Garret?
Come on HaD editors.
Oh wow, didn’t even notice the Gerret in there. Holy shit.
Are you another Garrett? There aren’t many of us :) In any case, it’s not a big deal.
— Garrett
I’ve now normalized the Garretts. Sorry about that ;-)
I am, and people forgetting the second t in my name is a pet peeve.
Hmm, it also seems to be Gerret.
Woops, too slow!
Two t, or not two t … That is the question!
Is it only my opinion that hackaday concentrates on useless, dumb and boring stuff last couple of month?
The focus isn’t the LED glasses, it’s the investigation of small microphone audio calculations leading into a design process. This can be used for more than just the example project. I reject the useless and dumb part of your assessment…but perhaps you have a point with boring if electronic design theory is not interesting to you.
Yeah, I have to agree. [solipso] obviously didn’t click through to the article because this one is anything but useless and dumb.
I find doing the math on the electret mic used in the project much more impressive than the usual “just solder it together and see if it works” method. It’s obvious from the demo that this work paid off too. Nice work Garrett!
Birtth certtificattes don’tt lie….. hahahah.