For music, the geometry is the same and direct-radiators are recommended. Bipole/dipole surround speakers are a hold-over from the DVD/cinema/Dolby recommendations.
The best set ups use 2 speakers unless you like gimmicky sounding and unnatural sounds of guitars and drums ect coming from the rears or sides were they DO NOT belong.
And speaker quality or type makes no difference unless you like this gimmick to begin whith imo.
Until the time that musicians start playing live all around you, this will remain a gimmick whith a few exceptions like DSOTM ect which were made for ss imo.
Ears...Antiphonal music has been around for centuries, but until now could not be recorded properly. Classical chamber music is sometimes performed "in the round" especially in small private performances. Many people have performed in orchestras, or chiors, and find the perspective of being in the midst of the performers to be natural.
Can it be a "gimmick"? Sure: but not always.
Kr4...theres ambience, such as used in the rear channels on Allison Krauss Live...and then there are distinct guitars, drums and other instruments coming directly from the rear or side channels...this is gimmicky and totally unatural to say the least... and definitly not ambience.
When I say hi rez surround is gimmicky, I mean 98% of what I have heard.
There are some recordings that seem made for ss, but in general, two speakers whith a more realistic soundstage is better than being in the center of the band ..so to speak.
Ears...Favorable mention of the rear channel use on an Alison Krauss multichannel recording strikes me as strange. On the recording that I have, applause is loudly recorded only in the rear channels. This is a gimmick...not what you would hear from anywhere other than the first row, in which case the performance sonic perspective would be different. The transition from performance to applause is very abrupt and unnatural sounding. IMHO of course.
Thanks from everyone who's responded. I just brought home a 6-ch. Emm Labs rig and find it everything but gimmiky. Two channel's great until one does surround correctly. Of course I'm listening to some wonderful artists on the Chesky label, and other well recorded in great acoustic spaces in DSD. The 'drums in the rear' stuff I resevre for folks who want to sit down and be 'impressed' from one or two songs with sounds flying around the room. Not very satisfying for long enjoyable listening sessions. In that regard I agree with the soundstage arguement.
Anyone come up with the answer to DVD-A placement? Seems I can't get a straight answer!
Five channel or multi channel music isn't fully perfected yet. I think a 12 year old could do a better mixing job then some of these sound engineers. With that said, I still think that these multi channel disk put CD's to shame. I'm ready to replace all my CD's with SACD's & DVD-Audio disk. It's time to move on.
I prefer full range direct radiating speakers for multi channel music.