Most coherent low volume speaker with very fast bass under 10k used?

I second the suggestions of Vandersteen speakers (I own 2 sets of Vandersteen 5's myself), for low volume performance I was even more impressed by Linkwitz speakers (http://www.linkwitzlab.com/) and he's got even more selection now. I met with Siegfried Linkwitz 10 years ago and even rented a vacation property from him for a weekend, which gave me the chance to listen to one of his personal Linkwitz systems for the weekend.  I was very impressed with how well they operated especially when I wasn't in the sweet spot and focused on critical listening.