To give each element of the Cosmic Array sound and IoT we are using the new Raspberry Pi Zero W. 

The Raspberry Pi Zero W doesn't have sound but with the addition of a low pass filter thanks to information on Adafruit Learn Blog this was quite straight forward.

Amplified by a  5V 3W Class D amplifier based in the PAM8403 which is cheaper to source as a fully assembled PCB than a chip on its own.

I needed 16  4 x 4 Raspberry Pi Zero W for an Art installation at Splash Adelaide and although there has been a one order per customer limit imposed by the Raspberry Pi Foundation on suppliers. 

Thanks to wonderful local Hackerspace Adelaide community we have been able to source 16  x Raspberry Pi Zero W for the task.