Line source and wave quide

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I have problem with living room(=listening room) even though I planned my house. Another side wall is halfly window and on the other side wall there are are two large door holes (no doors) plus firerplace. So the symmetry in sound stage is very difficult to meet.
I also like very accurate sound so I have been prototyping years many type of ways to control directivity.

Here is my current (not complete) system. It may have some interesting things. I hope this gives ideas to others too.

Speaker bases on line source looking implementation but it is not pure line source because the 3 drivers around tweeter handles mostly the range from 1k to 5k and the other drivers in line mostly the other part of 100-5k total range. Tweeter is 2" "ribbon".
The wave quide is effective down to 400Hz and narrows nicely horizontal beam. Now beef are the black areas on sides of the speaker. They are openings for resistance loading for line and makes the speaker guite constant directive between 100-10k. Speaker can be located right to wall behind them without any effect to sound because it is not radiating much to sides and back due to the resistanve loading and wave guide.
Bass is temporary closed box for 15-100Hz and will be replaced by resistance cabinet or other gradient radiator.
 

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Price is not an issue (yet) but it is not necessary at all. The directivity at lower freqs is boosted by the resistance box function so the line does not need to be longer.

There is one interesting thing to test. The filtering that slowly cuts the upper mid range from the most of the line source elements causes phase sift too which means that the 3 element on center are coming first and the other after that. Now if the 3 center ones could be delayd the vertical radiation pattern would be perfect. (I have tested similar approach earlier). The problem is to delay the tweeter also to maintain phase coherency between mids and tweeter. Delaying the tweeter is not possible by analog filter easily so tweeter "horn" should be made deeper. This might make tweeter horizontal pattern too narrow but it might be worth of testing anyway.
 
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