[thinksnow]

New house and new gear, but it's a big room.


I just moved in to a "new" house, originally built in 1953, the great room was added in the 80's and has full access via insulated crawl-space. The room is 35' x 18'8" and it has a lot of openings- doors & windows.


I'm upgrading from a JVC RX-6000V receiver with Sherwood SP-430S satellites & a JBL PB10 to a Denon 1910 and Acoustic Research Home Decor surrounds .


I want to run 14 gauge wire from a spot next to the fireplace, down inside the wall, through the crawlspace, then up to individual wall plates.


Like many, the problem I am facing is placement of the speakers. In the coming weeks, I will be replacing my 40" LCD panel with a 50-65" panel (it depends on the tax return total), so the couch is going to be fine positioned anywhere from 10-14 feet from the fireplace (not in use). Again, the room is 35x18, and the couch is roughly centered. The fireplace has a mantle that is almost perfect height if I were to follow the 1-2' above seated ear position, but to land the fronts on there, our ideal position would be a mere 8 feet back. On the other hand, once we start moving back, the windows and other features begin to compromise positioning of the side and/or rear surrounds.


The attachments are jpgs of the positioning as modeled in Sketchup.


Any input would be most welcome. It's way to late this evening, so I'll try too make sure this makes sense in the morning, and I look forward to any help you can muster.

 

[sdurani]

I would choose the 12 foot location, since it is at one of the 1/3rd points of room length (will help with smoother frequency response). This will put the front speakers at +/- 30 degrees, just outside the doors (large windows?) on either side of the fireplace, with the rear speakers at +/- 150 degrees, or maybe a little wider. The main compromise will be with the side speakers, which will have to be slightly forward of the listening position; though I don't think this will make a huge difference.


My second choice would be the 10 foot location, which would allow for the side speakers to be at +/- 90 degrees. The problem with being too close to the front wall is that it may cause neck strain from constantly looking up to see the screen. Moving back will help with that, but will start compromising surround placement.


Good Luck,

 

[thinksnow]

I was trying to take the "looking up all the time" factor into account- the mantle height is 4'3", so it's truly a consideration the closer you get.


I suppose I could mock up an 11' plan...

 

[penngray]



Quote:
Originally Posted by sdurani /forum/post/18209406


I would choose the 12 foot location, since it is at one of the 1/3rd points of room length (will help with smoother frequency response). This will put the front speakers at +/- 30 degrees, just outside the doors (large windows?) on either side of the fireplace, with the rear speakers at +/- 150 degrees, or maybe a little wider. The main compromise will be with the side speakers, which will have to be slightly forward of the listening position; though I don't think this will make a huge difference.


My second choice would be the 10 foot location, which would allow for the side speakers to be at +/- 90 degrees. The problem with being too close to the front wall is that it may cause neck strain from constantly looking up to see the screen. Moving back will help with that, but will start compromising surround placement.


Good Luck,

The length of his room is 18 based on his layout so 12feet is over 1/2 the length.


12 feet is the lenght I would choose though since its far enough away from the back wall still and far enough away and you are not close to the MIDDLE of the room which is the worst place to sit.

 

[sdurani]



Quote:
Originally Posted by penngray /forum/post/18209531


The length of his room is 18 based on his layout so 12feet is over 1/2 the length.

Like I said, it is at one of the 1/3rd points of room length. Divide the room length into 3rds; 12 feet will fall on one of those points. Frequency response is typically better at one of the 1/3rd or 1/5th points of room dimensions, and worse at even (1/2, 1/4) division points. The worst being, as you said, the middle of the room (1/2 room length).

 

[thinksnow]

So, going with the 12 foot plan:

• the front channels tuck right next to the windows on the front wall, at a height of 3'8" (supposed to be around ear height, right?).
• This puts them ~11'10" apart, and ~13'4" from couch center.
  
• the sides are sitting at about 105 degrees at a height of 5'4"-ish, angled slightly down.
• this puts them ~17'10" from couch center.
• The rear channels are at 135 degrees, at 5'4"ish
• this puts them 12 feet apart and ~8' from couch center

The sub(s) will go outside the two front windows.



Thank you for the feedback, folks. I think I'm ready to start cutting holes in my walls!


(one other consideration: get a projector and use all of the 85" diagonal above the fireplace...)

 

[flickhtguru]

Good plan although I would opt for the front left and right speakers to be on the outside of the windows above where you have the subs pictured to give a wider soundstage.


Also are you running a center channel? Where is that going to go?

 

[thinksnow]

Okay, I had thought about extending the width of the fronts, so thank you for confirming that it wouldn't be a bonehead move!


The center is going on the mantle, directly under the TV....or, hmmm, I could mount it just inside the fireplace so it's pretty much at ear-level and mostly hidden.

 

[sdurani]

Glad you're putting the front speakers outside the windows. The wider soundstage will sound nice with movies, but even nicer with music.


Any chance of moving the side speakers closer to the +/- 90 degree locations and the rears to +/- 150? It'll give you better side-vs-rear separation in the surround field.

 

[thinksnow]



Quote:
Originally Posted by sdurani /forum/post/18211013


Any chance of moving the side speakers closer to the +/- 90 degree locations and the rears to +/- 150? It'll give you better side-vs-rear separation in the surround field.

90 for the side is hampered on the left side by the doors. It could be mounted at

 

[sdurani]



Quote:
Originally Posted by thinksnow /forum/post/18213129


90 for the side is hampered on the left side by the doors. It could be mounted at

 

[thinksnow]

Is it bad to have the rears reciprocal to the fronts? That is, if the fronts are @ 33 degrees, would having the backs at 147 cause problems? Or would that not be an issue because the sound waves are 1) different & 2) traveling different distances, so there wouldn't be destructive interference?



PS: I appreciate this fantastic input. You are all wecome to drop by for a beer and a movie if you find yourself in the Cleveland area.

 

[sdurani]



Quote:
Originally Posted by thinksnow /forum/post/18213801


Is it bad to have the rears reciprocal to the fronts?

If you were using only 4 speakers, then yes: sitting in the middle of a symmetrical X-shaped layout hasn't fared well in preference tests (a single pair of surrounds needs to be spread much further apart to give decent envelopment). However, when using 7 speakers, it's not a problem. In fact, it works really well (because the side speakers are the ones providing envelopment). So having the rear speakers at roughly +/- 150 degrees does an excellent compromise: close enough together to anchor sounds firmly behind the listener; far enough apart to still allow stereo imaging back there.


BTW, these locations need not be surgically accurate. As long as they're roughly within a few degrees either way, you'll still get the intended effect. From the drawings of your layout, the result should sound spectacular.

 

[thinksnow]

Does it change the equation if I use a pair of PE Tritrix speakers for my front channels?


I've got the fronts and sides wired in the walls & just need to do the rear channels (and decide if I'm going to run the lines for the subs in-wall...or at all if the Tritrix make them superfluous) and I've got my new Denon 1910 waiting in the wings.


I have to think it can only make things better all around, right?

 

[Jim Hef]

I would also caution you to consider window treatments with your speaker locations along those front windows. If you plan for draperies of any sort, you're going to want to allow for that to the sides of the windows.

 

[thinksnow]

Yeah, I compensated for that with the left side surround between the side door and the greenhouse sliding doors- we hung curtains along that wall this weekend. That was for the south-facing side of the house, so the front channels will be along the west-facing wall.


Those side windows already have sheer curtains hung, though we may replace those with the heavier material we used on the south wall, or with cellular shades which would almost certainly be inside-hung. In any case, you make a good point to remind me, and I appreciate it.