Dear Richard
I never, never, never use a crossover to any main music speakers.
The idea is to bring up the sub to just start to add a pressure wave to the leading and trailing edges of the notes produced by the mains.
11 feet into the room may be the idea placement, if you subscribe to the audio physic setup mantra which is similar you are dramatically taking both walls out of the equation.
In my 25 years of doing this as a profession I have heard numerous setups which were similar.
This included a 2c3d Avalon Spectral system and of course a pair of Apogees played in the middle of a ballroom and boy that was a shocker.
So it all comes down to what works. There is nothing like sheer output that a good subwoofer provides.
I never, never, never use a crossover to any main music speakers.
The idea is to bring up the sub to just start to add a pressure wave to the leading and trailing edges of the notes produced by the mains.
11 feet into the room may be the idea placement, if you subscribe to the audio physic setup mantra which is similar you are dramatically taking both walls out of the equation.
In my 25 years of doing this as a profession I have heard numerous setups which were similar.
This included a 2c3d Avalon Spectral system and of course a pair of Apogees played in the middle of a ballroom and boy that was a shocker.
So it all comes down to what works. There is nothing like sheer output that a good subwoofer provides.