i have been told that jon dahlquist used quad esl 57 as his reference when designing the dq 10.
having owned the quads and listened to the dq 10s many times, i would say there are significant differences between them. thus it would seem that if you want to upgrade, you might consider a panel speaker rather than another cone-based speaker.
having owned the quads and listened to the dq 10s many times, i would say there are significant differences between them. thus it would seem that if you want to upgrade, you might consider a panel speaker rather than another cone-based speaker.