The way a speaker interacts with the room is a big part of how it sounds, for better or for worse. Imo it is possible to design a speaker to interact favorably with a very wide variety of rooms, including "terrible" ones. Several basic principles come into play:
1. The earlier and stronger a reflection is, the worse it is. So we want a radiation pattern that minimizes early reflections, which implies a fairly narrow pattern. Then ideally we want to aim that pattern in the horizontal plane such that it avoids early sidewall reflections. There are several different approaches to radiation pattern control which are viable, and it is up to the user to analyze his room and make an intelligent estimation of which radiation pattern(s) would minimize early reflections in his room.
2. The direct sound should be what sets the tone for how the speakers sound, which means we want the reflections to have the same spectral balance as the direct sound, or at least come close. (When there is a significant spectral discrepancy between the direct and reflected sound, the timbre can be degraded and/or listening fatigue can arise.) So we want the off-axis response to be smooth; that is, it should not start out emphasizing some frequency regions more than others. Given that a "terrible room" may be one which is overly reflective or overly absorptive, we might want the ability to adjust the spectral balance of the off-axis radiation without affecting the direct sound.
3. For all practical purposes there is no such thing as "the direct sound" in the bass region. It takes time for the ear to recognize those long wavelengths such that by the time the ears actually perceive bass energy, it has already reflected off the room boundaries multiple times. So in the bass region we want to take this inevitable room interaction into account as much as possible. Viable approaches include level-adjustable powered bass sections, user-selectable port tuning, EQ, a distributed multi-sub system, and some combination thereof.
Imo amp + speaker + room = "a system within a system". The speaker should interact favorably with both the amp and the room... even if the room is "terrible".
Ime fullrange controlled-pattern dipoles and horn systems designed to have very low coloration tend to work well in "terrible" rooms when set up correctly because their radiation patterns largely taking the room out of the equation, at least over most of the spectrum. In the bass region, which approach(es) make the most sense depends on the specifics of that particular room’s "terribleness".
Erik wrote: "
I remember running into an audiophile who refused to consider anything
about room acoustics. He bought speakers specifically for live,
untreated rooms.
"Anyone else? What was your solution?"
I have at times built custom speaker systems for very live, totally untreated rooms, using the principles described above. I can go into specifics if you'd like.
Duke
