@ptss - The simple answer is $$$. Mr. Dunlavy personally HAND TUNED every one of his speakers to achieve this tight tolerance. This tuning took into account the cross-over components AND the drivers in each cabinet. Doing custom tuning is not practical for anything other than a boutique enterprise. Why is it important to have tight tolerances? If you have a speaker with +/- 3db tolerance, you can have a 6db variance between frequencies coming out of your speaker. Is this important for realistic playback? You decide. Also, if speakers were made with +/- .5 db and music sounded funky in your room, you would know it's not the speakers causing the problem.
