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post #1 of 6 Old 05-28-2012, 02:37 PM - Thread Starter
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I can't seem to find this information and can't measure it at the moment because I don't have the system running yet.

I just moved and have the opportunity to arrange the room (no treatments, though) around the system rather than the other way. I want to minimize bass bleed into other rooms (at night - during the day I'll use a different listening position) and think that placing my listening position near the wall should allow me to turn the bass down (by switching MCCAC alignments and subwoofer EQ to my 'night' calibration).

My question/concern here is that I don't understand the nature of standing waves. I don't know if moving the listening position towards the wall will cause the bass ringing to increase to an unacceptable rate. If the level is adjusted to match the optimum day position, but near the wall to cut out bass bleed, will the ringing be better or worse than maintaining the optimum seat positioning and just turning down the bass? Based on a calculator, my expected problem areas will be in the 40-60hz range (12x15x10ft room).

Setup:
Pioneer Elite Vsx-91txh
Studio quality monitors for front (12" driver)
Floorstanding surrounds (12" driver)
Sonotube sub (18" driver, 19hz tune, can be lowered to 16hz with port attachment)
EP4000 for sub amp

I'll use this to update my setup progress with anything learn that I didn't know (after 10 years of doing this lol).

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post #2 of 6 Old 05-29-2012, 10:43 AM
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Your basic premise is flawed. Yes, moving speakers closer to the walls will increase the bass SPL in the room somewhat. But it's the SPL in the room that determines how loud the sound leakage is in adjacent rooms. So simply moving the speakers will not improve isolation, even if it seems like it might.

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post #3 of 6 Old 05-29-2012, 04:12 PM
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He's talking about moving the listening position not moving the speakers. It's a novel approach. With a separate MCACC eq setting for that scenario, it just might work well enough for your goal (late night with still decent bass).

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post #4 of 6 Old 05-30-2012, 09:53 AM
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^^^ Ah, yes I see that now. Sorry. D'oh!

The problem with sitting right up in front of the wall behind you is severe comb filtering. This could be reduced with thick absorption on that wall, at least for the area behind the seating.

I'll also mention that the bass boost, while real, is not huge.

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post #5 of 6 Old 06-02-2012, 11:06 AM - Thread Starter
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Thanks for the responses. I will probably end up doing that. @Ethan I've spent a lot of time on your site. Neat :P

Through random arrangements I've found that switching the fronts/surrounds made an improvement, but also found that my room is way too live. I've lost some detail and have problems at all freqs, especially the mids. It seems veiled and the only thing I can pinpoint this to is room reflections since EQ can't correct it.

My old room had a fully absorptive back wall, diffractive L/R, a pitched ceiling, reflective front wall, carpeted floors, and was a bit larger. In there I was able to look at the back wall and the soundstage remained at the front wall. Now when I do the same the soundstage shifts towards the back a bit.

I intend to hang some blackout drapes on the windows (front wall and left wall vs. the system) tonight, so I'll see what effect that has. Since it'll mostly be out of the direct reflect zone, I expect it to mostly lower reverb.

I have to get good imaging, depth, clarity, etc... before hooking up the sub will do much good.

I'll look into what I can do

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post #6 of 6 Old 06-06-2012, 08:18 PM - Thread Starter
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The drapes have allowed daytime darkness and seem to have deadened the room, but not excessively. It's showing promise... I seem to be lacking mids now instead of having them ring all over the place, so I'll look into that tomorrow wink.gif

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