Panipulator

Panipulator is an indispensable, CPU-friendly tool that lets you achieve accurate mix translation across various less-than-ideal playback systems. With simple streamlined controls, you can you check mono compatibility, speaker polarity, identify phase issues in multi-miked instruments, isolate speakers in mono, and more—and it’s absolutely FREE.

https://www.bozdigitallabs.com/product/panipulator/