LANDS

LANDS is a music visualizer

Reacts to any audio playing on the computer.

Esc to bring up menu, note that the strobe toggle can reduce strobe effects but there will still be some flashing.

Windows:
If you are playing the audio on the same computer you are running lands on you shouldn't need to do anything, it will work automatically.

If you are using an external line in or mic open the 'sound control panel', select 'recording' and in the properties of the device you are using check 'Listen to this device'.

Mac:

If you are using Mac you will need a virtual-audio loopback tool in order to allow LANDS to listen to the audio playing on the computer. BlackHole is an easy free option. 

In BlackHole Create a Multi-Output Device (Audio MIDI Setup → “+” → Multi-Output → tick your speakers/headphones and BlackHole 16ch.) and then Set that Multi-Output Device as the macOS system output. In Lands open the menu and select BlackHole 16-ch as the audio device.