I've got a number of comments here--I'm also a SH singer and have recorded our state conventions for the past three years. I've also given the problem of recording this type of music considerable thought and have experimented with it at local singings quite a bit.
I recently proposed the question of how best to record this genre to the pros at Gearslutz, though with a view towards using a 4-mic technique. I'm not sure this would directly relate to this specific stereo pair issue, but you might find it an interesting read, and you can see I'm also all about trying to create the effect of being in the middle of the square, though I'm not sure some of the pros could ever quite divorce themselves from the notion that this would be like recording a traditional choir:
http://www.gearslutz.com/board/showthread.php?t=107633First, I have to point out that I don't think Moke and bebo are quite on the same page, and that Dan's technique is a bit different, but I don't think it's been realized, yet. Moke is advocating a Jecklin-type solution (something I've tried myself several times), and thus recording with a stereo omni pair from a single location, say the tenor/bass corner, with both mics pointing in roughly the same direction diagonally towards the opposite corner (though with an angle of separation, to be sure). It seems to me that Bebo's (sorry--it's Jeremy, I see, now) diagrams indicate he's wanting the mics pointing in opposite directions, presumably from a location in the middle, with the mics pointed at opposite corners. Meanwhile, Dan Richardson's methodology require placing two mics in separate locations (a very widely split omni pair), thus rendering a baffle useless. Dan literally has one mic at the Treble/Tenor corner, the other at the Bass/Alto corner. Depending on the size of your square, I'm not sure this is possible with your Coresound "Binaurals" (won't rehash the somewhat misleading nature of that designation)--I don't think you have nearly enough cable between the individual mics and the battery box to do that. They likely could be modified, but this is something you'll have to think about before embracing Dan's approach. Do the mics have the clip option that Len offers? If so, that would make attaching them to something potentially much simpler, though likely without shock protection. While I think Dan's method is among the best solutions for doing this with a single stereo pair, keep in mind that it's a couple of steps removed from being what the leader really hears (where the loudest singing is likely right in front of you, with the tenors dominating the picture with a wide stereo image for that section). Throwing each section (especially the tenors and altos) into one or the other channel, with relatively little crossover, just seems a little weird to me when I listen, but again, it's a pretty good compromise compared to some other options.
The very first SH recording I made was with a surprisingly similar setup to yours. CS "binaurals" to battery box (and no, don't use the bass roll-off!) to a minidisc recorder. I checked the place it was to be held the night before (a new location we had never used before) and discovered there was a ceiling fan directly above the center of the square . . . And since this was in February, we weren't going to be using it. I clipped the mics onto different fan blades in what was essentially a spaced-omni technique, though I couldn't have told you that at the time. I should mention, too, that the fan was at least 2 ft. below the ceiling surface, so reflections from that didn't concern me overly much. My goal was to have the tenors across the front in the stereo image (and thus the altos, also, since it's not a surround recording), trebles to the left and basses to the right, just as if you were leading. So my mics were spaced in a straight line running from the middle of the trebles to the middle of the basses. The separation was perhaps 3 ft. or so. This was made more doable because our square was a bit oblong--that is the distance from the trebles to the basses was somewhat larger than the distance from the altos to the tenors. We had more tenors than anything else, anyway (which is typical, since it's the melody-bearing part), so the balance between parts was very, very good. I wished I had had better gear at the time, but it was still good enough that the singers talked me into getting it professionally pressed, etc--still available for sale
and it's on Steven Sabol's list of recordings with a brief review of sorts:
http://www.mcsr.olemiss.edu/~mudws/resource/chap05.html [about 1/3 of the way down the page, "With Songs and Honors Sounding Loud"] The only downside to being right in the middle of the square is that you can get a lot of the leader, particularly if he/she has a strong voice. The spacing I used helped with this a bit, but I've also tried suspending a jecklin disc from above in the middle of the square and didn't care for the overemphasis of the leaders. If using stands, or a stand with a jecklin disc, I think being slightly above seated head-height, pointed slightly down, might be better than exactly at head-height. The leader is well above head-height, after all, and you'll be a little less likely to get direct sound from one or two specific individuals this way.
I also have to say that I'd be careful with Dan's assumptions about what sections are louder than other sections. I think this has much more to do with how strong the individual singers are in each section, and of course how many you have--this would be especially true at smaller local singings. In my local group the basses are dominant if the key three or four of us are present. You'll know the characteristics of your own group best, of course.
Another issue you need to think about is how the singers are going to respond to this? Are they used to being recorded? Are they going to tolerate having to work around equipment? If you're a regular singer and they're expecting it, that would certainly go a long ways to making certain it will work. Dan's group is clearly used to how he does things and is willing to work with him (and I've heard some of the recordings he's done--that's how I finally really learned Claremont, actually--and they're very good). When I first checked with the powers-that-be about recording our state convention they were hesitant. They agreed finally, but only on the condition that I not impede the singing in anyway, and that I keep everything low-profile and out-of-the way. I think if I had had stands and cables on the floor that first time they might have balked. I ended up running the mic cables from the fan up to the battery box I had taped to the ceiling, then a long cable from the battery box to side wall of the room (all taped to the ceiling) down to the recorder. They're much more tolerant of me, now, but they know no matter what I try with regards to micing technique, it will not be any kind of imposition on them. I'm still not sure they'd be too happy about having a stand(s) in the square, but if it's OK with your singers, it will make your experience much easier.
This last point I'm going to mention just so that you're aware and can protect yourself if you so choose. If you're using the Denson book (the red book), and if you're going to distribute the recording at all--even for free--you are supposed to go through the mechanical license procedure with the Sacred Harp Publishing company and pay the fee. They hold the rights to recorded performance of much of the music in that book (though not all, oddly enough--it's complicated). Again, what you do with this information is your business, but it was very much an issue and a pain-in-the-butt for the recording I did that became "commercially" available. Not sure what the situation is for the Cooper book. Shoot me a PM if you want to know more, but if it's just for your own use (and doesn't get beyond your local group of singers) I doubt you have much to worry about.