audiofox said:
I'm pretty sure that the 17W75 mid woofer, which is used in the 52SE (and most likely also in the 52) is designed for a sealed enclosure, but I'll have to check my old Dynaudio specs to be sure. If that is the case, it may be simply a matter of closing up the vent to eliminate the overexcursion problem.
The mid/bass drivers in standard Audience 50/52 and 52SE's are completelly different, exept the size. I have had the Audience 50 for some years (now they are owned by my close friend, and I regularly have access to them and listen again), and to my experience under no circumstances those drivers are botoming out, even when driven in fairly unsane listening level (e.g feeling the bass by stomach), used by fairly biig amps such is Rotel RB1090, etc. The enclosure is the same, the bass port also identical with 52, with the only obviously thicker fron MDF.
audiofox said:
BTW, it appears that the main differences between the two speakers is the tweeter and the crossover-the 52SE has the D260 Esotec, a VERY nice tweeter (vs the D28/2 in the 52), and probably has a modified crossover to better match the D260.
That's correct. The Audience 52SE and Contour 1.3mk2 are the same drivers and in both the mid bass is problematical, again, irrespective of amplification used. The smaller the damping factor of the amp, the worse the bottoming out.
audiofox said:
...did you test the 52SEs with and without the foam port plug? There is a noticeable difference in response with and without the plug, and I wonder if the plug is enough to take care of the problem.
I tested the Contours as mentioned, but did not acheive any benefit, exept loosing the wall reinforcement. Both 1.3mk2's and 52SE's sounds best with open bass reflex, and with enough space around them. And, yes, either model needs especially high current/high damping factor amps, and some Krells of KSA or similar series would not be inapropriate, but again, who will spend so much for amplification of relativelly cheap speakers?