Tune your entire sound system in under five minutes with the innovative auto-tuning capabilities of the Alpine OPTIM™8. Using the PC App and a mic kit (sold separately) or the OPTIM8 IOS App and built-in microphone on an iPhone® 10 or newer, measure, correct, and tune your system to your desired listening preference through fast and easy guided tuning instructions. Manufactured under license rights from Eilex International, LLC. Eilex PRISM and VIR Filter are trademarks of Eilex International, LLC.