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DougMac
04-01-2008, 06:56 AM
OK, I know I'm driving you crazy with questions. I'm almost finsihed framing my HT and I'm at a point where I need to make some decisions that will determine how I wire before sheetrock is applied.

Here's the setup:
The HT is 16'Wx 18'D. I'm using front projection with a screen 8'W x 54"H. There are 2' square columns in the left and right corners on the front wall (to hide immovable plumbing). and I'm building a 1' soffett above to form a proscenium. That leaves 2' on either side of the screen, where the mains will be placed. I plan for the fronts of the mains to be slightly in front of the column face, which will place them a little more than 2' from the screen wall. Primary seating will be 11-12' from the front wall.

My preliminary layout has the bottom of the screen 30" from the floor. That places the midpoint of the screen 57" from the floor and the top of the screen 84" (7') from the floor. There'll be a foot between the top of the screen and the 1'H soffett and the room ceiling will be 9'.

I have considered placing Sierra's on the pedestal stands, but they're only 24" tall. In that case, it would make the most sense to place the center below the screen, which would be almost on horizontal axis.

The other plan would be to find suitable wall mounts (e.g. http://www.amazon.com/Wall-Ceiling-Speaker-Bottom-Mount/dp/B000JKYMSM/ref=sr_1_13?ie=UTF8&s=hi&qid=1207057206&sr=8-13) and mount them on the sides of the columns and turn the speakers 90 degrees to the front. The mounts would be placed to put the speakers midpoint on axis with the screen midpoint. With this scenario, the center would be the same vertical distance from the mains if placed either above or below.

Lastly, pets and rugrats aren't a factor regarding the safety of the speakers.

The advantages of the floor standing speakers would be they would be closer to ear level. The possible disadvantages would be that the center is low and I've heard some folks don't think that's optimum. Also, they'd be much lower than the surrounds, which will be flown. I don't know if that's a factor.

The advantage of mounting the speakers would be a better WAF and the center could be placed above. The disadvantage would be further from ear level and the center would be 7' high, if that is a disadvantage.

Thoughts?

Thanks,
Doug

debo
04-02-2008, 04:53 AM
Horizontal axis is perfect. Shoot for that!

DougMac
04-02-2008, 06:20 AM
Horizontal axis is perfect. Shoot for that!
Thanks for the reply. After nearly 50 looks on no response, I was beginning to think I had won "Stump the Band".

My gut tells me horizontal axis. When my wife realized they wouldn't stick out in the room more than a couple of inches past the column, she was much more accepting. We'll see what happens when I start tweaking the position!

When I bought some used HTM-200's, I forgot to mention the purchase before they arrived. I've been instructed that she must be by my side when I click the "Purchase" button for the rest of the speakers!

That reminds me of an old Dave Gardner line:
"Do you know women are smarter than men? Why yes. They've always posessed what men have been seeking."

Doug

chas
04-02-2008, 06:40 AM
Is an acoustically transparent screen an option at all?


When I bought some used HTM-200's, I forgot to mention the purchase before they arrived. I've been instructed that she must be by my side when I click the "Purchase" button for the rest of the speakers!


Boy does that sound familiar...:o

DougMac
04-02-2008, 07:56 AM
Is an acoustically transparent screen an option at all?

I think it's unlikely because of room design and economics. It sure is temptng, though!

Current plans are for DIY laminate screen made from either Wilsonart Designer White or Formica 948 White. Matte laminates make great screens and are relatively inexpensive, a 5x8 sheet costs $66. With a masonite substrate, frame and mounting hardware, a 108" diagonal screen runs a little over $100. Looks like acoustically transparent screens that size start at ~$700.

Also, as someone not entirely convinced grille cloth doesn't affect sound, I can't bring myself to putting a speaker behind a screen. It seems either sound or image or both will not be optimum. I'd love to see some response curves with Sierra's (or really any speaker) measured with no screen in front, then a high quality acoustic screen.

Doug

chas
04-02-2008, 08:14 AM
Seymour AV has some measurements of their screen material available on their website:

http://www.seymourav.com/screens.asp

DougMac
04-02-2008, 09:51 AM
Seymour AV has some measurements of their screen material available on their website:

http://www.seymourav.com/screens.asp

Thanks for the link! I've ordered a 2' square sample of the material. It looks like the DIY material would run ~$200 for the screen size I'm planning. In the scheme of things, another $150 for the screen won't break the bank. The cost would probably be less, since I could use home made brackets attached to the back wall instead of buying stands or wall mounts. If I got really cheap, I could order the Sierra's in natural since they'll be hidden.

As soon as I get the sample, I'll do a blind listening test with an HTM-200 behind to see if I hear a difference.
Doug