I have improved the Audio Spectrum Analyzer. By increasing the number of MSGEQ7's and offsetting them I now have 21 frequencies per channel. In order to display all of them the sign had to be turned sideways.
This first version supports 8 LED strips:
This second version supports two sets of 8 LED strips for a total of 16 strips.
I can even do an oscilloscope on the WS2812 LED sign.
This is the schematic of the foreign made MSGEQ7 shield that I used. Then I made my own shield that is offset to add the additional frequencies.