Possible bookshelf upgrade

Hello to all.
Here is my question. In my bedroom I have as my mains a pair of Definitive Technology Studio 55. I am thinking of upgrading. I run these with a Marantz SR5010.One candidate is the Paradigm 15b. So, would I be gaining much doing this? They are in a 5.1 system. My budget is up to $2000. I have heard the Nola boxer, which is very nice. I am just not sure if at this range it would be significantly better. Thankx in advance for all advice.

I'd look at Focal 906's.  Truly amazing if you can get them set up right in the room.  

The paradigms are great too, but I'd rate the Focal a notch higher.

I'd also be sure to listen to Ryan and Scansonic as well -- but at the $1,500 price point, the 906 Focal is just unfairly good.
Well, if I am not mistaken, the DF 55s sell for ~$500. So with a $2000 budget you can most certainly get an improvement. 

Do you use this system for 2 channel music listening as well as for 5.1 movies? To me the value of the upgrade would depend on this.
Yes, it is part of a 5.1 system. I am also changing my primary listening  area as well. I have questions about that. . Not sure where to post that as I have questions about speakers and electronics.
Perhaps a pair of Zu Omen Bookshelf? I own them for my office and they are quite nice. Also, less than $2k.
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There are lots of speakers that can perform well in both stereo and front L/R duties.  The thing is that as you increase the quality of your speakers the Marantz will quickly become a bottleneck for performance, especially in stereo -- which is why I asked how important 2-channel is to you.  $2000 speakers are more befitting of a separate stereo pre and amp or a good integrated.  These can be incorporated into your existing system very easily.  Hope this helps, and best of luck. 

Thank you. The Marantz AV receiver will stay in the bedroom. So good advice that perhaps not reaching for the stars in an expensive bookshelf is sound advice. That would then give me lots of choices instead of heading near the $2000 point.

The KEF R300's are a fantastic bookshelf (3 way) that falls a little under your $2k price point ($1800 retail).

Also, Tannoy is going through a future model update to the Definition Series, and as such, the current models are on sale.  You can get a nice deal on a pair of Definition DC8's, and they are quite good as well (and normally around $2900 retail).

****KEF and Tannoy dealer disclaimer
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