If you are talking about speakers for personal or studio use, I would recommend the Even Tria system. It has a subwoofer with two satellite monitors (you will need stand for these) all powered by a triamped system. It originally listed for $999, but it now available for $499 form various on-line music dealers. This is what I am using with my I30 and I have been completely satisfied with the range and quality of the sounds produced by this system. If you are talking about a system for live performance, for my money I would go with any of the Mackie powered mixers and JBL speakers.