Please suggest bookshelf with best bass response under $4000 pr.

Dynaudio Special 25,s go down to 35hz with plenty of articulate punch. Need room to breath with that 8 woofer, good electronics, careful room placement and you'll be a very happy camper.

Wow-- a lot of suggestions, here. Thanks to all. This is a lot to sort through. The Silverlines use Dynaudio drivers, BTW. 

@audiotroy : your assertion that I need to go out and hear speakers brings up another point. I haven't bought any gear based upon in-store audtion for many years, following an initial experience with a system that sounded good in the store but was terribly fatiguing once I got it home. 
With all due respect, I don't see how that can work. Even if I were to lug my integrated, cdp and cables to a store, the room sound would remain a huge variable in the equation. If I'm missing something, please explain.  

@willemj : many thanks for your unflagging efforts to find a simple solution!  What you suggest does sound do-able. 

Stuarik,

Yes the room plays a huge variable, however, the multitude of choices that are being mentioned is mind boggoling.

For example we sell five or more brands of mini monitors, KEF, ATC, Paradigm, Athom, PSB, Legacy.

When a person comes to my shop as long as we keep the variables the same you can hear the overall personality change of the speakers and each different companies product brings something else to the table. 

In that way it makes it easier for a person to go to the next step which would be an in home demo if that is what is required.

You may love a pair of newer Dynaudio's or you may not as the newer speakers are much more transparent than yours. So unless you love trying and buying, trying and buying, etc, over and over again, going to a good dealer if there is one in your area or going to a regional show may help you find the model to take the next step with or flying  into a city with many different dealers such as New York and demoing models in your price range you will have a very hard time of this. 

Your tastes may vary as to the rest of the posters and you may love or hate whatever people are recommending, therefore the only way to know is to go and listen to as many models that make sense with your price range, matching equipment and decor that will work for you.

The path is your own, and so is your methodology and you are right that different stores are going to produce different results the idea is to try to gain a perspective as to the overall qualities of a brand as a starting point.

Dave and Troy
Audio Doctor NJ

Sonner will release lower price point product lines at Axpona 2018. This is a trigger down technology from Allegro product line. A stand mount speaker for 4k, two way floor standing around 6k and two half way floor standing around 8k.