I suspect one of the reasons that simple equations seem to under estimate the distance to sit from speakers is because the calculations assume a point source for the speakers. The larger the speaker or the speaker array then the less accurate the calculations will be.
For Dds_hifi: be sure that you use open cell foam for acoustical absorption. The problem with small rooms is that since they are small there isn't much space for absorbing materials. In a 12x12 room I would expect that you will experinece a strong resonance at about 45Hz at the walls if your speakers go that low or if you have a subwoofer. Absorption will not solve that problem if it exists.
My room is aproximately 14x15 with an average 9.5ft ceiling with a sitting position against the wall. The resonance at 37-42Hz is unbearable. Playing something like Clapton's "Unplugged" is an instant headache. The only reasonable solutions are to use a notch filter(1/3 ovtave or parametric equalizer) for the subwoofer input signal or turn the sub off for music. I chose the equalizer and it works fine. Good luck!
For Dds_hifi: be sure that you use open cell foam for acoustical absorption. The problem with small rooms is that since they are small there isn't much space for absorbing materials. In a 12x12 room I would expect that you will experinece a strong resonance at about 45Hz at the walls if your speakers go that low or if you have a subwoofer. Absorption will not solve that problem if it exists.
My room is aproximately 14x15 with an average 9.5ft ceiling with a sitting position against the wall. The resonance at 37-42Hz is unbearable. Playing something like Clapton's "Unplugged" is an instant headache. The only reasonable solutions are to use a notch filter(1/3 ovtave or parametric equalizer) for the subwoofer input signal or turn the sub off for music. I chose the equalizer and it works fine. Good luck!