My room is 21' wide and 19' deep, with a ceiling rising from 6-1/2' high in front to c. 12' at its peak a couple feet short of the back wall. My 989s' panel centers are c. 6-1/2 feet from the front wall; their outside edges are about 4' from the irregular side walls. I sit with my head about 10' from the centerline of the speakers, and they're about 9-1/2' apart center-to-center...about 7' inside edge to inside edge They are toed toward the listener slightly but 'cross' far behind me.
I had to experiment more with getting them farther from the front wall than anything else. Every time I moved them farther off the front wall, the soundstage got deeper. I now get soundstaging and imaging better than I've ever heard anywhere (but I don't get around much to hear other fine-sounding systems*). Playing my absolute-fave Boult/Holst Planets, the tamborine and xylophone sound as if they're about 50' behind the speakers.
I bought an Eminent Technology LFT-12 centerchannel speaker to replace my much-loved, modified Aerial CC3B. I installed it yesterday and began comparing its sound to that of no centerchannel speaker at all...what some call phantom-center. I thought my system IN TWO-CHANNEL placed sounds in the middle relatively well, that is, instruments and voices that I thought should be in the left-to-right center of the image were well focused in the center, not too big, not too small, etc. It's SO good that using my 5.1-channel system with phantom center sounds BETTER (with a couple movies, anyway) than using any centerchannel speaker.
So the 989s sound GREAT, at least to me and my golden-eared goodbuddy.
Let me know if you have other questions.
* I get around so little, I've never heard any system sound better overall than mine is currently sounding.
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