Unfortunately, the best sounding systems at low volume are horn systems that are also physically big in size so they create other placement problems. There are other somewhat bass restricted higher efficiency systems that also sound pretty good at lower volume.
Dipole speakers are also great for keeping sound levels down outside of the primary listening area. Such speakers, like quad electorstatics, tend to focus sound within the listening area they are aimed at, so that there is MUCH less sound spilling outside of the listening area (the out of phase front and back signal cancel at the sides, large panels tend to have less fall off of soundlevel with distance than speakers that are closer to being point sources).
I have owned large panel electrostatics (Martin Logan) so I can personally say that they are much better than conventional dynamics in reducing the amount of sound outside of the listening area.
Dipole speakers are also great for keeping sound levels down outside of the primary listening area. Such speakers, like quad electorstatics, tend to focus sound within the listening area they are aimed at, so that there is MUCH less sound spilling outside of the listening area (the out of phase front and back signal cancel at the sides, large panels tend to have less fall off of soundlevel with distance than speakers that are closer to being point sources).
I have owned large panel electrostatics (Martin Logan) so I can personally say that they are much better than conventional dynamics in reducing the amount of sound outside of the listening area.