Room Mode/Screen Size (1 Viewer)

[Articfox918]

I'm very new to the whole HT scene but I have been frantically researching as I get ready to build. A little background before I ask my question. I will be working with a completely blank slate in the basement so I have nearly every option under the sun available to me. I have a rough idea of my room which will be 24' X 14' X 8.5' I refuse to start building until I have a firm grasp on what I am going to do. I have been researching like mad and I know Screen size is not based off of what space you have but rather where you are siting. During my research I stumbled across a Room Mode calculator by Harman. I entered my room data and here is what the tool spit back at me.

So my question is can someone shed a bit more light on this for me. If I am reading and doing it right I should have my seating at about 12' which would be dead center of the room, correct? I plan on having 2 rows of 4 seats with a bar behind the back row of seats. If my above statement is correct do I split the difference between seat locations? Does it matter? Or do I only worry about where the person using the theater all the time(ME) will be sitting most of the time?

 

[Stephen_J_H]

This seems to only be acoustic calculations, which are definitely a consideration, but there are other questions that are more pertinent to the home theatre elements.

1. Screen size--if your front wall is 14' wide by 8.5' high, how big of screen are you wanting to install?
2. Viewing distance--this will do more in terms of speaker placement than the room mode calculations above, as you will want your surround speakers [for 5.1 surround] to be just behind your ears and slightly above them. If you have back speakers [7.1 surround], you'll want sufficient distance from the back wall to your seating area for the effect to be heard. If you go to the next level, which is "object-based" audio, you'll want to factor in the positioning of any ceiling mounted speakers
3. HD or 4K display? Are you going projection or flat panel? A flat panel will automatically reduce your distance to screen; as well, to appreciate 4K, your optimum distance from the seating area will actually be closer to increase perception of detail. With a 4K projector, your front wall will easily support a 12-15' diagonal screen if you have a projector with the necessary lumens to produce such an image. The recommended viewing distance for 4K is 1-1.5 screen widths, which with a 12' diagonal screen would be anywhere from 10-15 feet. For 1080p, your ideal viewing distance is anywhere from 15-25 feet, putting your sweet spot at between 12-15 feet for a 12' screen.

Just some starter thoughts....

 

[bigshot]

Figure that you want to avoid reflection points. Think of your room as a pool table with sound bouncing off the walls. A listening position in the middle of the room puts your listening position right at the primary reflection point of the wall. Not good. Split the difference 2/3s back from the speakers.

 

[amirm]

So my question is can someone shed a bit more light on this for me. If I am reading and doing it right I should have my seating at about 12' which would be dead center of the room, correct?

Oh definitely not. You are reading the Harman graphs incorrectly. The place to *avoid* is where you see those troughs/nulls which in your case is at 12 feet. Those cancellations are very hard to fix. Move your seating position to where there are mostly peaks as those can be fixed with equalization. Just a foot or two makes a big difference.

As to who optimize for, definitely for yourself first . That said, if you use multiple subwoofers and signal processing, you can get a pretty wide sweet spot. See my article here: https://www.audiosciencereview.com/forum/index.php?threads/subwoofer-low-frequency-optimization.15/