Your avr should have come with a calibration mic. Put the mic where you'll be mostly sitting. Have it sit on a stool or chair so it's about your ear height. Have the avr menu on screen and connect the cable to the mic input. Should start automatically. It'll play test tones to calibrate volume and speaker distances. During this time need to be very quiet so try not to laugh because the tones can be kinda funny lol. After that, audio should sound very intune where you sit.