As akg described well, the 2wq subs avoid the major historical problems with sub integration. I run a pair of 2wq subs with Quad esl speakers and the sound is so good i stopped reading speaker reviews. The speaker system seems to have unlimited potential so i just focus on other parts of the system for upgrades. The integration is amazingly seamless especially considering the speed of the quads and difficulty mating to electrostats. I like the sound much better with the 2wqs. The acoustic space is much more apparent especially on live recordings with the subs and obviously the extension is night and day ... I cant say enough about Richard Vandersteens design on these. I do not understand why everyone is not talikng about 2wq subs more often.
