<font color='#000000'>With $5 k to play with you have lots of choices. Any specific models I or anyone else might suggest would have a dozen alternatives that would make you happy. That said, the recommendations you'll no doubt get here would make a good start for your search.
Also, with a $5k budget for those relatively few components any salesman you talk to is thinking "commission bonanza" so take their recommendations with a large grain of salt.
Do your homework, spend lots of time listening. There's simply no substitute for it. And spend the bulk of the dough on the speakers. Don't fall for the high-priced amp pitch. While I envy a $5k budget myself it ain't in the cost-no-object class of course. Get (say) a Rotel instead of a (say) Bryston or the like. [edit: if by an amp you meant a subwoofer amp, ignore this and get a powered sub like the Velodyne or Hsu, below.]
IMO, Magnepans have many fine qualities but there are better choices. I think most would agree that Velodynes are among the best subs so you can't go far wrong there. But if you want to alter the balance toward higher-end main speakers -- always a good idea -- take a look at Hsu subs for one example. When you're paying $2500 or so for a sub, you're paying a lot extra for that extreme bottom end response that will seldom be missed in the vast majority of program sources. If I had the $5k in my hot little hands, I'd spend $4500 on the best, most transparent and refined main speakers I could find and $500 on something like a Hsu VTF-2 (if I have the model # correct) sub.
If you are overwhelmed with the complexity of choices and decide to settle on a Bose Waveradio, you may wish to donate the leftover cash and the gear you already have to the Rip Van Woofer Disadvantaged Audiophile Fund. See my Website for contact info.
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