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

My harbeth c7es3 have great bass response.   Way better than the 30.1 imo.   Just a fantastic speaker all around!   Plus it matches up with most amps.  I do prefer a solid state preamp with them.  

I owned a couple pairs of Totem Mani-2’s and if you have enough power from a good SS amp, you will get very good bass. I had a 200 watt Classe CA-200 amp at the time and they needed more power. I teamed them up with the McIntosh 1000 watt monos and they sounded amazing. 

The Mani 2 is a stunning speaker but know you'll need a seriously beefy amp to feed it. If it doesn't double down from 8 -> 4 ohms don't bother. Rewarding at the end of the day though!!

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.