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#### thegratingone

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I am planning to use a 9' diagonal 16x9 screen (so just under 8 feet in width). I plan on placing the first row about 12 feet back (THX recommended distance).

My question is, how far to the right/left is reasonable for one to sit (i.e., how wide can the seating rows be?)?

I had planed on the seating rows being about 12 feet wide. That's 4 feet more than the screen, so the end of each row would be about 2 feet past the screen to the right/left. As the person sits in the center of the seat, that would mean the viewer would be (probably) about 1 foot to the right/left of the screen (maybe 1.5 feet past as the screen is a drop under 8 feet). Does that seem o.k.?

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#### jcebedo1

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I went to century stereo which has a similar set up to yours. THey are using a 110" diagonal 16:9 screen, yours is 108" diag. Front seats are about 11' or 12' back, and there are 3 large recliners. On the back row, which is about 16' or 17' back, there are 4 lagre recliners.

If I were you, I will try to get the front seats to be closer together and the back row (if you have a back row), can be wider since the back has less of an angle problem than the front.

James

#### amillians

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My protractor is a little rusty, but it sounds like your setup would yield around a 21-23* off axis viewing angle, which seems like it would be objectionable without doing somelike like a curved row using arm wedges (who would want to crank their neck 23* to the left/right for two hours to watch a movie?). Also, depending upon the screen you plan to use, that 21-23* off axis (which would be lessened somewhat by using a curved row) could have a fairly substantial impact on the effective screen gain from those seats--the higher gain the screen, the worse the effect would be for those seats.

#### Art Sonneborn

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I agree with Alex. The further out you go and the closer you are the more you want to turn toward the center of the screen.This isn't a big deal for a few minutes of TV but after 45 minutes let alone a few hours you will be uncomfortable. The curved row concept helps a lot there. I used to think that the curved rows in home theaters were just for looks but after going to an HT meet where the host had curved rows, I realized that the seating was much more comfortable than my straight rows. I later swapped out some arms to get curved rows.

Art

#### thegratingone

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Quote:
 Originally posted by amillians My protractor is a little rusty, but it sounds like your setup would yield around a 21-23* off axis viewing angle, which seems like it would be objectionable without doing somelike like a curved row using arm wedges (who would want to crank their neck 23* to the left/right for two hours to watch a movie?). Also, depending upon the screen you plan to use, that 21-23* off axis (which would be lessened somewhat by using a curved row) could have a fairly substantial impact on the effective screen gain from those seats--the higher gain the screen, the worse the effect would be for those seats.
I get about 26-27 degrees. My protractor is VERY rusty, but I calculate it as follows. It's 12 feet to the row. The row is then about 12 feet across, so 1/2 that is about 6 feet in each direction. That makes the angle about 26-27 degrees coming off the screen (i.e., it's 26-27 degrees from looking straight ahead from the middle of the screen to looking at the far right seat). This is the same angle the person will have to crank their head. I guess my 26-27 isn't so different from your 21-23 (and my figure is coming out worse for me!).

However, I do plan on using arm wedges for a curved row, so I don't think the neck cranking is a big deal. I'm more concerned with the effect on the picture (i.e., losing the gain) from the sides. Stewart says that the effective viewing angle for the Firehawk is 100 degrees (I think, based on their diagram, they're quoting 2x the angle we're studying, i.e., they're quoting it going out in both directions). Thus, based on our calcs I need about 50 degrees, and Stewart quotes it at 100 degrees. I assume some of their 100 degrees is puffery, but that I have a decent margin for error (obviously I'm not sure though or I wouldn't have posted this!).

Jeez I hope I'm getting this right... Of course, anyhow, the middle seat (mine) will be fine

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#### thegratingone

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Quote:
 Originally posted by Art Sonneborn I agree with Alex. The further out you go and the closer you are the more you want to turn toward the center of the screen.This isn't a big deal for a few minutes of TV but after 45 minutes let alone a few hours you will be uncomfortable. The curved row concept helps a lot there. I used to think that the curved rows in home theaters were just for looks but after going to an HT meet where the host had curved rows, I realized that the seating was much more comfortable than my straight rows. I later swapped out some arms to get curved rows. Art
I really should've mentioned that I am planning on using curved rows...

I'm more concerned with viewing the screen from an angle (while looking straight ahead of course because of my nicely curved row!).

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#### amillians

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Perhaps I was subconsciously doing the math with the understanding that you were assuming a curved row...yeah, that's the ticket.

Either way, the half gain of the Firehawk is 28*, which means that the people on the ends of the front row are going to be in negative gain territory (maybe 0.8 or so???) with the proposed setup. For whatever reason, Stewart still hasn't published a gain chart for the Firehawk, so call them with any concerns before writing that check (I guessed at 0.8).

#### thegratingone

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Quote:
 Originally posted by amillians Perhaps I was subconsciously doing the math with the understanding that you were assuming a curved row...yeah, that's the ticket. Either way, the half gain of the Firehawk is 28*, which means that the people on the ends of the front row are going to be in negative gain territory (maybe 0.8 or so???) with the proposed setup. For whatever reason, Stewart still hasn't published a gain chart for the Firehawk, so call them with any concerns before writing that check (I guessed at 0.8).
I'm unfamiliar with the concept of 1/2 gain. If the gain on the Firehawk is 1.35 straight ahead, is 1/2 gain mean at 28* you get 1.35 * 50% or 0.675?

Help!

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#### amillians

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Quote:
 Originally posted by thegratingone I'm unfamiliar with the concept of 1/2 gain. If the gain on the Firehawk is 1.35 straight ahead, is 1/2 gain mean at 28* you get 1.35 * 50% or 0.675?
Correct. The half gain of a screen material is the number of degrees off axis where the gain is down 50%.

#### Briands

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One issue that has not been mentioned is speaker location. I've noticed that the near side surround speaker becomes very "obvious" when setting very near the side. If your room is much wider than the screen, though, this may not be as noticable.

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