Audio Reactive LED Strips Are Diabolically Hard
scottlawsonbc.com
Audio Reactive LED Strips Are Diabolically Hard
1–10 of 76 posts
Re: Audio Reactive LED Strips Are Diabolically Hard
#2Interesting. I'm currently in the process of building something with a audio reactive LED strip but didn't come across this project yet.
The WLED [1] ESP32 firmware seems to be able to do something similar or potentially more though.
Edit: Oh wait, that project needs a PC or Raspberry PI for audio processing. WLED does everything on the ESP32.
Re: Audio Reactive LED Strips Are Diabolically Hard
#3Interesting. I'm currently in the process of building something with a audio reactive LED strip but didn't come across this project yet. The WLED [1] ESP32 firmware seems to be able to do something similar or potentially more though. [1] https://kno.wled.ge/ Edit: Oh wait, that project needs a PC or Raspberry PI for audio processing. WLED does everything on the ESP32.
Check out the MoonModules fork/variant of WLED too, it has much better audio reactive user mods and visualisation options https://mm.kno.wled.ge/ than the main project.
And yea, I agree with the article. In my past I've also dabbled in audioreactive for LEDs and it's fiendishly difficult to make anything interesting.
Make it react too much, and it's chaos, and inversely when the algorithm reacts less the audio, it's boring.
And in all cases it's really not easy to see what the leds are doing in correspondence to all the complexity of music.
Re: Audio Reactive LED Strips Are Diabolically Hard
#4IANAE but I would go for electric circuit, not electronic software that steers the led. I think that nowadays, with the LLM support it can be easier and better to optimise it for the sake of latency.
Re: Audio Reactive LED Strips Are Diabolically Hard
#5Interesting. I'm currently in the process of building something with a audio reactive LED strip but didn't come across this project yet. The WLED [1] ESP32 firmware seems to be able to do something similar or potentially more though. [1] https://kno.wled.ge/ Edit: Oh wait, that project needs a PC or Raspberry PI for audio processing. WLED does everything on the ESP32.
Yeah WLED does it fine, I've built a few and it works well.
Re: Audio Reactive LED Strips Are Diabolically Hard
#6More than 20 years ago or so I made a small LED display that used a series of LM567 (frequency detection ICs) and LM3914 (bar chart drivers) to make a simple histogram for music.
It was fiddly, and probably too inaccurate for a modern audience but I can't claim it was diabolically hard. Tuning was a faff but we were more willing to sit and tweak resistor and capacitor values then.
Re: Audio Reactive LED Strips Are Diabolically Hard
#7Always been very interested in audio-reactive led strips or led bulbs, I've been using a Windows app to control my LIFX lights for years but lately it hasn't been maintained and it won't connect to my lights anymore.
I tried recreating the app (and I can connect via BT to the lights) but writing the audio-reactive code was the hardest part (and I still haven't managed to figure out a good rule of thumb or something). I mainly use it when listening to EDM or club music, so it's always a classic 4/4 110-130bpm signature, yet it's hard to have the lights react on beat.
Re: Audio Reactive LED Strips Are Diabolically Hard
#8IANAE but I would go for electric circuit, not electronic software that steers the led. I think that nowadays, with the LLM support it can be easier and better to optimise it for the sake of latency.
If you want minimum latency, you want the input side of an traditional vocoder, not an FFT. This is the part that splits the modulator signal into frequency bands and puts each one through an envelope follower. Instead of using the outputs of the envelope followers to modulate the equivalent frequency bands of a carrier signal, you can use them to drive the visualizer circuit.
That can be done with analog electronics, but even half an analog vocoder needs a lot of parts. It's going to be cheaper and more reliable to simulate it in software. This uses entirely IIR filters, which are computationally cheap and calculated one sample at a time, so they have the minimum possible latency. I'd be curious if any LLM actually recognizes that an audio visualizer is half a vocoder instead of jumping straight to the obvious (and higher latency) FFT approach.
Re: Audio Reactive LED Strips Are Diabolically Hard
#9Are these available commercially for consumers?
Re: Audio Reactive LED Strips Are Diabolically Hard
#10The mel spectrum is the first part of a speech recognition pipeline...
But perhaps you'd get better results if more of a ML speech/audio recognition pipeline were included?
Eg. the pipeline could separate out drum beats from piano notes, and present them differently in the visualization?
An autoencoder network trained to minimize perceptual reconstruction loss would probably have the most 'interesting' information at the bottleneck, so that's the layer I'd feed into my LED strip.