Hi Tom,
I just finished a major room treatment project that included measuring the bass response (20Hz - 300Hz) of my listening room using the Real Traps test tones (1Hz steps). I tried many different positions for my Larger sub and RM30Ms including having the 11" woofers fire in and out. After recording and plotting far too many room frequency response curves what I learned is that there is no "Best" position. There are some positions that are definitely bad. However, there are also a lot of positions that give a fairly flat room response. However, each position has its own peaks and valleys. Do you want your bass to drop off at 25Hz instead of 30Hz? You can have that, but the trade off is a 5dB deeper valley at 75Hz. There is no such thing as a free lunch.
I would definitely experiment with the placement of your speakers. Every room is different and you never know what will work in your room until you try it. I found the best 'compromise' position for my room is to place the sub in a front corner, raised 2 feet off of the floor, and the RM30Ms backed up so that they almost touch the front wall, 11" woofers facing out. Also the RM30Ms are aimed directly at the sweet spot, not set up to cross 3 feet in front of the sweet spot. While these positions are not logical, they do yield a reasonably flat room response curve. In addition, my audiophile friends who assisted me on numerous weekends agree that these positions sound the best.
I use two of the 500 watt Dayton Loudspeaker plate amps to drive my Larger. The single band parametric equalizers were very helpful in smoothing out the low bass (20-80Hz).
If you want to get the best out of your RM30Ms, my recommendation would be to try as many different positions for your speakers as possible. Try all positions, even radical ones. Keep copious notes so that you know what you have tried and what the results were. Eventually, you will see patterns develop and you will have a better feel for the acoustics of your room. If you are really ambitious, download the free test tones from Real Traps and use your Radio Shack SPL meter to measure the frequency response curve. I set up a spreadsheet into which I typed in the raw data. The spreadsheet would add in the correction factors for the non-linear response of the RS SPL meter and then show the data as a graph. Being a visual person, seeing the room response curves as a graph really helped me to understand the acoustics of my room. YMMV.
Have fun and keep experimenting.
