I have a few screen caps of rep Ron Cornelius somewhere & from memory (we're in trouble now) I think he said once that people place them near and far from the wall to good effect; and another time that they should be ~ 12" to 16". I'll post some of his thoughts later...maybe.
Right now, the back corner of my angled speakers are 16" from the wall and 99.5"(8' 3.5") apart center to center.
The chair is a Deco-style, home-theater type recliner so the exact distance from speaker to ear varies slightly, but I just measured to the point where the bottom of the seat back meets the back end of the seat cushion (at a point laterally centered) and got 169"(14'1"). I then reclined the seat to a typical degree and, using the tape measure as an impromptu plumb bob, got another ~6". There is ~7' from the back of my head to the wall behind. The overall best results for toe-in, IMO is for lines from the center of the speakers (on a pair of XRT1K that's 56 tweeters !!) to a point just behind mein head. I just remembered that there is a diagram in the XRT1k Owner's manual that pretty much looks like that on page 8-figure 3.
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See below for attachment of that diagram and PDF of the manual or link to it from McIntosh.
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...Note that Mcintosh does not give actual measurements in degrees or distance.
... Note that a quick glance at the lines on figure 3 would seem to be showing toe-in and that it is converging on the listener's nose. Those lines
do not show toe-in. Look at the speakers. I believe that McIntosh is implying that the speakers might ought to be converging at a point behind the listener;
waay behind. I tried that and other angles and what I said above, so far, seems to work best for me in my room. I believe that there is some thought out there that line arrays can or should be used sans toe-in; that sure didn't work for me - no Mac magic.
Forgot to say that my room is, nominally, 24' wide by 25' to 28' long with a 6' opening, floor to ceiling, to a hallway that is 8' deep by ~ the 25' width. in other words, the entire room/hallway addition is 24'x36'. The speakers are at the middle of the 25' length.
If I did the math correctly and punched all the buttons accurately, the volume of the room is ~6530 cubits...uh...cubic feet and it's open to that ~2560 cu ft hallway.
That no doubt sounds like a room that is of a house that is much bigger than I have; it's a major % of the entire house. I built that addition by my lonesome ~ 30yrs ago; makes my arthritis tingle thinking about it.
No, I've never worked as a carpenter unless you count a little pickup work I did for a few months for a modular house outfit ~ 35 ? years ago.
Oh, I don't think that the ceiling is much of a factor (line array, don'tcha know)
, but it's high. 8' at the speaker wall going up from there to 18.5' at the highest point, which is not at the center of the 24' width( it's 15.5' there ) due to the purlin construction. 18.5 high is at the top of the clerestory windows (9ea. 4'x2' sliders along the 36' length of the addition) Speaking of those windows, it reminds me of why I usually cover the speakers when not in use. Those windows(south facing) let full, direct sunlight on the speakers in the winter and a good amount of indirect light the rest of the year. Considering what the speakers cost, I imagine that new grills cost more than many people would pay for a pair of speakers. I just now, for the first time, looked closely at what it would take to replace only the grill cloth and decided that I would need 6 hands, at least, to do it myself; glad I've been covering them.
I find that, in this setup, playing music at typical spl in the 80 to 84db range at 14' (peaks are higher) that the VU needles, except on peaks, rarely see the right side of 45 watts.(MC452) I also have found,testing with earmuffs, that a continuous, steady bass beat can be played at a steady 900 watts before the Power Guard's beady little red eyes start flashing to that beat. I did this a couple of years ago and if I measured the SPL, I don't recall the figure.
These monsters are designed to be used with the monster MC1.2kw. I wouldn't be surprised to learn that those red LEDs would come on at 2400 watts.
I imagine that these speakers, driven by the MC1.2's, would pressurize a room the size of, say, a typical high school gym; the 452's might be adequate.
http://www.mcintoshlabs.com/us/Produ.../xrt1kom02.pdf