You are really approaching this with some nice thinking.

Your concerns about the bass cutoff are justified, but look deeper into the specs. A quality speaker conservatively spec'd to have a 50HZ cutoff may actually produce more output at 40HZ than an agressively spec'd lesser speaker that claims to go to 40HZ. Try and find out the output relative to say 1KHZ, where they are both down by 3dB, 6dB, etc. Apples to apples. In terms of speakers high or low, think about movie theaters for your answer. I think so long as the speaker is far enough away from the listener's ears, room reflections and dispersion will diminish the effects of exact placement - especially if you have one of those A/V units with the microphone auto-setup.

As you pointed out, you can mitigate bass cutoff issues with perhaps a small subwoofer. No need to make it super loud. Just to add a subtle "bottom" to round out the sound, you might find enjoyable. You can always crank it up temporarily when there is the odd opportunity to not disturb your neighbors.

Other than that, I think your layout is fine, except that you will need to do some balancing to compensate for the difference in your left and right speaker placements. Your left speakers, near the corners of the room, will produce more bass and have reflections off the side walls, whereas the right speakers will produce a bit less bass, and have no side wall to reflect from. You can compensate for this with your A/V receiver and by playing with the speaker angles relative to the listening position. Another option would be to make the front speakers a bit closer together to make the dispersion patterns more similar (i.e. left front further from side wall). Try to rig up an experimental setup before permanent placement, if you can.

Seems like a nice place. I wish you all the best. 

I would go a bit over the head. IMHO the realism of the ambience being created by the synthesized echos in the rear channels is degraded when the listener gets direct radiation from the speaker. When you get localized signals such as a plane flying by, the difference in loudness of the speakers alone will be enough to cause the sensation of the plane moving over you, even if the speakers are not pointed directly at your ears. I think the front speakers should be angled towards the center of the listening area if possible. Together with the center speaker, they will then focus your attention on the screen, and only when a lot of energy is coming from the rear (bullets buzzing by, etc.) will you even be aware of the rear speakers (unless you switch them off - then it will be like - "what happened?"  ).

But by far the best, and only valid test is your own ears, and what you like. Nothing beats simply messing with the setup until it pleases you. So again, I encourage you to plan for a temporary installation that allows you to tweak placement before you drill holes, etc. In my case, I have the advantage of thick wood-paneled walls. If I change my taste, I just drill new holes and fill the old ones. And all the speakers, except the subs can be pivoted to reflect differently into the listening area.

And ... nice painting ... 

I would also not be to hasty on your front channel speakers at ceiling level if it can be avoided. 

You will actually have better sound if the front (l,r) speakers are at about head height while sitting.

Also, if you want to lessen some of the reflection, you may consider some heavy drapes to cover the windows.


Just a thought

Quoting CharlieM:

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I would also not be to hasty on your front channel speakers at ceiling level if it can be avoided. 

You will actually have better sound if the front (l,r) speakers are at about head height while sitting.

If i place them at headlevel, the other one will be infront of the screen, and looking from the front they wouldnt be placed symmetrically. Which annoys me way more then it should I could place them a bit below headlevel, but i would still have the problem of not being symmetrically placed. Also they take too much space on the floor.

Quoting CharlieM:

Quote:

Also, if you want to lessen some of the reflection, you may consider some heavy drapes to cover the windows.

I have the sunblock curtains covering the window walls entirely. If you look the floorplan the dashdot line indicates the curtains.

Quoting stephan.klose:

Quote:
A bit below headlevel won't be a problem... Just use your receicer and the mic to take the new measurements.. Or you enter them manually..
But a little asymetrical placement is still way, way better then putting them on the ceiling.. You can do that with rear speakers but I would really avoid it with the front ones.

Well in june i switched the back/front speakers around, to test it. And so far sound only improved (previous front speakers were too low, below the couch arm rest). But i dont understand how ceiling level is worse. You either place them below or above the screen, your eyes are normally pointing to the middle of the screen, so wouldnt the distance be equally "bad"?

current setup: