Some things don't change! Back to ASR after some months away, and there's still debate about room DSP!
But not unreasonable, as it's probably one of the remaining areas in acoustics and psychoacoustics where the jury's still out.
Just some anecdotal 5 cents, since
@svart-hvitt mentions the D&D 8C, and the room. As you know I got them a couple of months ago, and I became very enamored. Because of this "moving into the new house" project which seems to extend to eternity, I've had them in a small and suboptimal room. I compared how it was to listen to them in this room and in a larger and better room downstairs, and the difference was large. Much better in the larger room. Still, I perceived the fundamental presentation to be similar. And all my listening had to take place in the small room in the attic.
But after some time, I began to miss my previous speakers, the AVI DM10 monitors, in spite of how impressed I was by the 8Cs. The AVI's are speakers which I really really love, but it's not clear to me why I perceive them as being so good. Speaker design wise, they are not spectacular on paper. They are active and have very steep crossovers (48 db), so that's good, and the drivers are very high-performing and expensive, relative to their price point. But they are two-ways (bad because of intermodulation distortion), rectangular and boxy (bad because of diffraction), non-DSP based (bad because there's no advanced EQ), and their dipersion is not even with frequency (tweeters and woofers have different dispersion at the crossover point). Without the addition of a subwoofer, they don't have enough extension and authorithy in the bass. All of this deviates from what I believe to be best practice in speaker design. At the same time, I do perceive them to have a "clarity" and a level of detail, combined with a certain "smoothness" in their presentation, which is almost unsurpassed to my subjective ears.
Would I perceive it like this in a blind-test? I have no idea. Is it due to simple things like frequency response and dispersion pattern? Perhaps. Is it just that I have gotten used to how music sounds on them? Maybe. But anyway, this is my subjective impression. So one week ago, I finally moved the 8Cs to their new home, where they will soon be installed. In the meantime, I unpacked my old AVI's from the basement, and put them in the same listening room. I was curious as to how they would sound there compared with the 8C's. And voila, everything I had found myself secretly longing for was once again there! The unmatched clarity, the silky smoothness, the very inviting way of presenting music. The basic character of the AVI's, which I had heard in the previous setup with them and really enjoyed, was there in this new room as well. I have found myself enjoying music even more with the AVI's than with the 8Cs in this room, even though the 8Cs easily surpass them in some areas - better imaging/soundstaging farther away from the speakers, more bass extension and superior dynamics.
Why? Perhaps it's due to the bass extension of the 8C's, which may overpower such a small room. Or perhaps it's that the AVI's are bass light, which may make the higher frequencies appear "clearer". Or who knows, perhaps the engineer at AVI really know what he's doing. According to AVI, using a waveguide will by necessity color the sound, and they think that anything that messes ever so slightly with the direct sound from the drivers is a trade-off that is not worth it, and the overriding concern in speaker design should be to optimize how it sounds on-axis. Personally I'm also not sure about using Class D amps for the high frequencies. Whatever the reason, I do perceive a difference between the 8Cs and the AVI's, that is there independent of the room.
This is all anecdotal of course. But my personal experience so far indicates that we can indeed separate out the room when we listen, and that speakers will have their "sound" even in different rooms. Just like instruments btw. This isn't to say that room eq will necessarily be detrimental. I have heard good results with room eq/DSP, and I have heard corrections I didn't like. I think a large reason for why room DSP may sound subjectively good is that it performs "speaker EQ", which can be important for bad speakers, and that it can take care of level and distance differences between speakers. Beyond that, whether it's good or not good to adjust the direct sound in order to adjust for irregularities in the indirect sound, on that I'm still agnostic.