I use them with B&W 801 III and Krell system, and I can never go back to stock Xovers. Granted the Matrix are great out of the box, but the weak link is the Xover. They become more musical, much quicker and cleaner. I heard the 802 Nautulis and am keeping my 801 III with North Creek Xovers. I hope this helps you, and feel free to contact me.