I have a pair of BW 805 Nautilus speakers and was looking for a change which would give me a bit more bass than the stand mounts I currently have in a compact floor standing set.  

My current set up is a McIntosh D100 preamp with a McIntosh MC 2105 power amp.  I've been considering ProAC and Spendor.  Any other suggestions would be greatly appreciated.

I'd be willing spend up to $4000 but am unsure whether there's anything out there that would make a significant improvement in a compact floor standing set vs the 805's.

My room dimensions are 15' wide x 20' long.  
The usual progression is to a 2.5 way speaker. More efficiency, and deeper bass.  See what Monitor Audio has for you, but you may find them initially too laid back.

Of course, room acoustics matter, as does speaker placement.


I was considering the Montor Audio gold 200s, , Proac 20DRs /30R and the Spendor A4s .  the last two are not 2.5s but the cabinets should improve the bass.
FWIW, I went from B&W CDM-1NT (which I think are same vintage (2000ish) as your 805’s) to Spendor D7.

A4’s are nice. Not sure how they’d pair with Mc (possible combo would be on warm side??).

Haven’t heard any of the others on your list.

Maybe the Monitor Audio could pair pretty well with Mc, but just a guess.

Do you like your A7s? and what are you driving them with.  Also how would you describe their sound.  I plan on demoing them this weekend.
I have D7, not A7.  Love them.  Driving with Audio Research DSI200. 

If you read my previous posts (just click on my name) I go on at length about them, haha, probably too much....

In the Spendor A4/A7 thread I list the differences between A and D series, for example.
I’m familiar with the N805s, and used in your price range I think you’ll get significant improvements across the board from Vandersteen Treo, Joseph Audio Profile, ProAc D30, Silverline Sonatina, and Nola KO.  To me, these can do everything the 805s can do and do it better, but perhaps the most important difference is that all these reach down and communicate the emotion and soul of the music such that he 805s sound sterile and lacking life by comparison.  Just my experience and opinion FWIW.  Best of luck in your search. 
The proac D20r are excellent speakers but I'm not sure how they would pair with your McIntosh solid-state amplifier. They are a easy load to drive with a amplifier problem is they do like tubes. They have plenty of bass if their positions correctly. Happy Hunting
I went from a pair of B&W Signature 805’s to the Proac D-30R’s. As nice as the B&W’s were the Proac’s were a huge step up. I find the D-30R to be a much more engaging and musical speaker. Also they are easier to drive and a bit more room friendly than the B&W’s.

Good luck
How about a pair of Dynaudio Confidence C1s? They are no longer made, but they can be had used for less than your price. I've never owned them, but heard them once in a store demo and was astonished by how much bass they delivered. (I used to own B&W Signature 805s.)
Just a thought.
-- Howard