Originally Posted by Jon AA
I thought it was pretty well accepted that room treatments for a 2 channel music listening room are going to be quite different than those for a multi-channel/movie room (for many of the same reasons I was describing different speaker attributes take on different levels of importance).
I'm reminded of an interview of Dennis Erskine (designer/installer of $100K+++ home theaters) where he flat out called the two "incompatible" and explained why. Here's the interview, this particular question is around the 55 minute mark:
Now, "incompatible" might be a bit harsh as I expects he sets the performance bar for his clients a few notches higher than I'll ever hope to achieve spending mere pennies... But the reasons he describes sound pretty valid to me. Anyway, it's pretty clear he wouldn't think two channel music listening is a good indicator of performance for a multi-channel system.
I got around to listening to this podcast - his initial statement that a theater can't work well for 2 channel and that a 2 channel room can't work for home theater is later clarified to a 2 channel room can't work for theater. His reasoning though is a bit strange, as he feels a theater room doesn't have the reflectivity and ambiance of a 2 channel room, and that surround channels can be used to build that back in. Perhaps if we get into the fringe of 2 channel purity folks, lots of room reflection and smearing is desirable, but for my purposes, I am still focused primarily on the direct sound from the speaker, whether it be for stereo music or surround sound. Stereo imaging, sound stage width, and phase cues are part of the recording, not features of the room. The room is not creating something that isn't there. That said, L & R placement within the room is critical to extract these characteristics properly, and it is true that a lot of theater I see don't have L & R placement that is very suitable for stereo music listening. This is a major reason why I left a 4' space open behind my AT screen, why my mains aren't pushed out all the way to the sides of the room, why I still use toe in, and why my seating is based on the golden triangle.
He went on to tell a story of one of his clients who was willing to build two separate rooms for each purpose, but found the 2 channel in his theater to be good enough.
To bring this back in, soundstage width and height, as well as stereo imaging depth and placement are important not only in 2 channel listening, but also movie watching. When the front soundstage feels larger and more engaging, the entire movie screen seems active with sound, not just 2 or 3 spots on the screen.