Where to begin?? Well first I don't think anyone would argue that siblance can be caused from poor (on sometimes purposely done--as Zaikesman points out) source material. What can you do about this--nothing. Siblance can also be caused by poor source components (or D/A conversion). Siblance can be caused by poor power that affects one or more of your components. However, in this case, it seems clear that the majority of the problem and the first place to attack it is the room. After that, you may begin to attack the other areas, but it's not going to do much good until you get the big problem fixed first.
Stehno makes an interesting point about how we perceive sound. We have done a lot of research in psycho acoustics and it's a very interesting topic. Not many do this type of work and it's not often published since there is little funding on it. We are exploring new avenues in this area and are finding that perception is dominant in listening environments over steady state measurements, but fortunately the 2 do correlate.
As Stehno states, we know when we are in a church or empty space and compensate for that. That is psychoacoustics, and he is right. The human ear has the ability to distiguish reflected tones past 35 milliseconds or so as separate from the original tone. When the reflection arrives at the ear within 35 milliseconds we can not distinguish it (for the most part) and integrate it as part of the original tone. These short time reflections add to ambiance and general spaciousness of the soundstage. The longer the reverberation times the larger the space. The louder the reverberation the emptier the space. People could walk into a space blindfolded and have someone talk to them and could give a rough estimate of the size of the space and whether it was empty with hard surfaces or not.
Now, that being said, our hearing compensation is that to tune out those later reflections past 35 milliseconds (and much longer in large spaces) and we attribute that to the noise floor. Peter D'Antonio of RPG has done a very interesting auralization of this. He has done it for many buildings, but for one it was an entry way into an office building or hotel I believe. The auralization has several voices speaking in the background and then one that is louder--speaking to you. Without room treatment the intelligibility of that speaker is very poor as it is masked by all the other voices reverberation around you, but once the room is treated the intelligibility goes way up. This might seem very obvious, but it makes an important point. Long time reflections must be attenuated or they impede on the intelligibility of the original sounds being produced. This directly translates to music, but is even more important, because we are listening critically to details including very low level and short timing cues. When reverberations of other sounds are lasting too long, they are masking those details. The reverberations longer than say 50 to 60 milliseconds will come across as sibilance.
Stehno makes an interesting point about how we perceive sound. We have done a lot of research in psycho acoustics and it's a very interesting topic. Not many do this type of work and it's not often published since there is little funding on it. We are exploring new avenues in this area and are finding that perception is dominant in listening environments over steady state measurements, but fortunately the 2 do correlate.
As Stehno states, we know when we are in a church or empty space and compensate for that. That is psychoacoustics, and he is right. The human ear has the ability to distiguish reflected tones past 35 milliseconds or so as separate from the original tone. When the reflection arrives at the ear within 35 milliseconds we can not distinguish it (for the most part) and integrate it as part of the original tone. These short time reflections add to ambiance and general spaciousness of the soundstage. The longer the reverberation times the larger the space. The louder the reverberation the emptier the space. People could walk into a space blindfolded and have someone talk to them and could give a rough estimate of the size of the space and whether it was empty with hard surfaces or not.
Now, that being said, our hearing compensation is that to tune out those later reflections past 35 milliseconds (and much longer in large spaces) and we attribute that to the noise floor. Peter D'Antonio of RPG has done a very interesting auralization of this. He has done it for many buildings, but for one it was an entry way into an office building or hotel I believe. The auralization has several voices speaking in the background and then one that is louder--speaking to you. Without room treatment the intelligibility of that speaker is very poor as it is masked by all the other voices reverberation around you, but once the room is treated the intelligibility goes way up. This might seem very obvious, but it makes an important point. Long time reflections must be attenuated or they impede on the intelligibility of the original sounds being produced. This directly translates to music, but is even more important, because we are listening critically to details including very low level and short timing cues. When reverberations of other sounds are lasting too long, they are masking those details. The reverberations longer than say 50 to 60 milliseconds will come across as sibilance.