How did you treat your main room?
I did not use any sound absorbing panels.
I set the room dimensions as optimally as the layout of the home permitted.
I used wool carpet.
The objects in the room were arranged to produce as much irregular reflection as possible. The equipment wall makes for a highly irregular surface.
The the windows on the opposite side also scatter the reflections. The rear wall houses my LP collection. There is a window, which adds a little liveliness there, as well as giving a good view of Benedict Lake.
However I think the major reason for the bass clarity, is the fact that it is an aperiodically damped TL system. These systems have a bass that is quite unlike reflex or closed box systems. It is very different in many ways. The bass reproduction is inherently non resonant but at the same time deep and powerful. So the Laplander drumming in the first movement of Aho's first symphony, is literally as "tight as a drum".
There is no ring or carry over. It sounds like bass drums all round the room.
Tymps sound like they really do, the bass strings sound just like they should as well as piano bass strings. The "being there" realism is quite uncanny. The lack of boom and muddle in the bass line, allows for clarity of texture through out the frequency spectrum.
Many visitors have heard this system now, and the clarity, balance and realism of timbre of all instruments and voices is always the focus of their comments.
We had close friends from Minneapolis visit this weekend. They brought along a couple, both high powered lawyers, visiting from California. They are opera buffs. They frequently listen at a close friends house who apparently has an extremely costly system. They watched opera here for a significant part of the visit. To say they were astonished was putting it mildly. I put on a first class production of Mozart's Marriage of Figaro, from Glyndebourne. A stellar cast under Haitink, the whole production beautifully filmed and recorded. They were totally taken in with the realism of the sound.
I think there is another reason why TLs are kind to rooms, and that is a phenomenon that organ builders refer to as the encircling nature of the sound from speaking pipes. By that they mean that pipes fill a room in a very uniform fashion, unlike a usual speaker system, guitar or piano. A pipe organ has a remarkably uniform spl. throughout the space, whereas the others loose spl, very quickly as you put distance between you and the source.
A TL is a very specialized pipe. Much more of the total output comes from the pipe mouth, and over a far greater frequency spectrum than from a reflex port.
This phenomenon of encircling has never received much attention outside the realm of organ builders. However after an experienced organ builder demonstrated the truth of the phenomenon, I have often wondered if that is a big reason as to why TLs seem to maintain clarity in a wide variety of listening rooms. In fact I believe the nature of the output from reflex ports is a root cause of lumpy bumpy bass reproduction.