[nanidin]

I used a library I found on github for a similar project - here's their demo page: http://deibelman.github.io/dart-mic/demo.html

For my project, I was charting the dominant frequency for fun.

[hoddez]

Whoa cool thanks for sharing that. This could have been very helpful, and still might be. I'll have to check it out and see what they did differently and how the performance compares.

[nanidin]

Underneath, it uses DSP.js also, so I'd imagine it's pretty similar. I am able to get autocorrelation & FFT frequency results out & graph them at about 50hz without any optimization on my rather old laptop in Chrome.