If there is sufficient time delay between the first-arrival sound and the onset of significant reverberant energy, we can have the best of both worlds - imaging and envelopment.
Reflections done right are beneficial from the standpoint of envelopment and spaciousness and a sense of immersion, timbre, clarity, and liveliness. They can preserve the three-dimensionality of the recording, something that reflections done wrong will degrade. The benefits of reflections done right are why acousticians do not design anechoic chambers for recording studio mastering rooms, nor for recital and concert halls.
Relying upon the direct sound from the speakers to deliver all reverberant information (and suppressing anything that involves the room) looks good at first glance. But what's not obvious is the fact that the worst possible direction for the dominant reverberant energy to come from is direct from the speakers. Controlled listening tests have shown that when reflections come from the direction of the speaker only, the ear/brain system tends to interpret them as coloration. As the direction of the reflections' arrival detaches from the speakers, the ear/brain system interprets it as ambience and spaciousness. As we add time delay to the onset of those reflections, the ambience and spaciousness improve, and any degradation of sound source localization decreases (there are exceptions to this, but it's true for most decent home listening rooms). As we increase the relative amount of energy in a spectrally-correct, late arriving, decorrelated, and diffuse reverberant field, the benefits mentioned increase, up to a point. It is possible to overdo it... imo Amar Bose overdid it.
So I'm not saying there's no tradeoff in sound source localization precision vs spaciousness from reflections done right, but the loss in localization is small, and in return we get significant benefit in several areas.
I would like to comment on one statement above:
"Note that there are also reports (also from reviewers) mentioning that the walls of a (small) room have simply disappeared and what was left was a beautiful large stage. This happens when the amount of secondary reflection is minimal and this is exactly the point that I am making."
That can also happen in a small, untreated room with a loudspeaker system that gets the reverberant field right.
From a show report by a reviewer, of a system that arguably incorporated "reflections done right", in a 13' by 19' hotel room, with ZERO acoustic treatment:
"Really nice, big spacious open sound. Again, it actually expands beyond the physical confines of the room. I dont think ANY other system at the show has been able to pull that off."
That was written at RMAF 2013, Sunday afternoon, after the reviewers (there were two of them) had nearly finished making the rounds. If anyone is interested I can provide a link to the full commentary by the reviewers, wherein you can tell they are experiencing many of the other benefits I mentioned.
For the record, I never set out to build a speaker with particularly good imaging. My focus is always timbre. Just so happens that, far as the reverberant field goes, what's good for timbre can also be good for imaging.
Imo, ime, ymmv, etc.
Duke
Reflections done right are beneficial from the standpoint of envelopment and spaciousness and a sense of immersion, timbre, clarity, and liveliness. They can preserve the three-dimensionality of the recording, something that reflections done wrong will degrade. The benefits of reflections done right are why acousticians do not design anechoic chambers for recording studio mastering rooms, nor for recital and concert halls.
Relying upon the direct sound from the speakers to deliver all reverberant information (and suppressing anything that involves the room) looks good at first glance. But what's not obvious is the fact that the worst possible direction for the dominant reverberant energy to come from is direct from the speakers. Controlled listening tests have shown that when reflections come from the direction of the speaker only, the ear/brain system tends to interpret them as coloration. As the direction of the reflections' arrival detaches from the speakers, the ear/brain system interprets it as ambience and spaciousness. As we add time delay to the onset of those reflections, the ambience and spaciousness improve, and any degradation of sound source localization decreases (there are exceptions to this, but it's true for most decent home listening rooms). As we increase the relative amount of energy in a spectrally-correct, late arriving, decorrelated, and diffuse reverberant field, the benefits mentioned increase, up to a point. It is possible to overdo it... imo Amar Bose overdid it.
So I'm not saying there's no tradeoff in sound source localization precision vs spaciousness from reflections done right, but the loss in localization is small, and in return we get significant benefit in several areas.
I would like to comment on one statement above:
"Note that there are also reports (also from reviewers) mentioning that the walls of a (small) room have simply disappeared and what was left was a beautiful large stage. This happens when the amount of secondary reflection is minimal and this is exactly the point that I am making."
That can also happen in a small, untreated room with a loudspeaker system that gets the reverberant field right.
From a show report by a reviewer, of a system that arguably incorporated "reflections done right", in a 13' by 19' hotel room, with ZERO acoustic treatment:
"Really nice, big spacious open sound. Again, it actually expands beyond the physical confines of the room. I dont think ANY other system at the show has been able to pull that off."
That was written at RMAF 2013, Sunday afternoon, after the reviewers (there were two of them) had nearly finished making the rounds. If anyone is interested I can provide a link to the full commentary by the reviewers, wherein you can tell they are experiencing many of the other benefits I mentioned.
For the record, I never set out to build a speaker with particularly good imaging. My focus is always timbre. Just so happens that, far as the reverberant field goes, what's good for timbre can also be good for imaging.
Imo, ime, ymmv, etc.
Duke