A volume unit (VU) meter or standard volume indicator (SVI) is a device displaying a representation of the signal level in audio equipment.so in this tutorial lets build a VU meter using Arduino
just add an aux cable to pin a0
connect anodes of less to pin 2-13
connect cathodes together and connect to ground
connect aux cable a0 and ground
arrange in a round shape and solder
if you have any doubt, please let me know.