How to create a grid of points reactive to audio

I am quite new to three.js. I am trying to make a visualisation reactive to audio (music). How can I make a plane with grid like structure of circles/squares, where the size and/or brightness regulated according to the sound frequency.

You can use this example: three.js examples
The AudioAnalyzer node gives you back an array of magnitudes at each frequency which you can write your code to tie to different values of your objects.

made a mini example for this once, not points but lines - it’s the same principle though