Rear speaker distance

Review the speaker placement recommendations at the following websites:

http://www.dolby.com/consumer/setup/...ide/index.html

http://www.dts.com/Consumer_Electron...gurations.aspx

http://www.thx.com/home/setup/index.html

^ +1

Based on your drawing, you look to be over 12' away from a 46" TV. That's *way* too far away. Check this viewing distance calculator:
http://myhometheater.homestead.com/v...alculator.html
Consider moving your listening/viewing position closer to the display, or consider a bigger display.

Also, the surrounds in a 5.1 system are the "side surrounds" not the rear surrounds. Be sure you connect them to the proper "surround speaker" connections on your receiver. They appear to be placed properly for your current listening/viewing position. However, if you move your LP forward, move the surround positions forward also.

BTW, in your system, the "primary" listening position, (aka the "sweet spot"), is the left-most position in the sectional. In fact, I would move the sectional out so that that seat is exactly centered on your display and the center channel speaker. Then perform all calibrations from this position.

Craig

That calculator is a bit ridiculous. It tells me I should be no more than 4 feet away from my 32" TV in order to see the difference between SD and HD. I currently sit about 10 feet away and have no trouble seeing the difference.

Sitting 12 feet away I should have a 96" screen for the recommended THX spec?

You guys are misunderstanding the calculator. It doesn't tell you how close to sit to be able to distinguish SD from HD. It attempts to fill a specific "field of view". Yes, to get that you need to sit pretty close to a small screen. But try it and see if you don't get a more immersive experience. And a 96" screen at 12' is just about right. My 128" screen is superb at 13.5'.

BTW, the calculation recommended by the store comes 7.667' The maximum THX viewing distance from the calculator is 7.2'... pretty close, but I would recommend the THX "recommended" viewing distance of 5.1'. (Obviously, that won't work in your room, but you get my point.)

Craig

Down at the bottom there is a section for SD and HD viewing distances.

So you're saying the calculator tells you the distance where the screen will fill the recommended 26 degree viewing angles? I can see how that would help with immersion, but I imagine it would be fatiguing on your eyes to sit that close.

Ah, you're right. I never even looked at that because I haven't had a "Standard Def" TV in about 10 years.


I have a 37" LCD in my office. I sit about 4.5' away from it, which is right at the THX recommended viewing distance. I watched the Bears beat the Vikings last night and I had no eye strain whatsoever. Just a lot of glee a the Vikings losing!

Craig

The dts link shows multiple layouts for 7.1 instead of just rear wall placement. Do those methods make a difference? Will any av receiver that handls DTS adapt to the layout upon the auto configuration?
Thanks!

No, those "alternate" layouts are not supported by any specific surround algorithm. The auto-setup routines can't determine where you have your speakers placed. They can only determine how far away the speakers are from the measurement mic.

I don't know why DTS even has those alternate layouts in their recommendations. They don't make any sense. Use the one that is labeled 7.1 Standard

Craig

In my receiver researching today, I did find that some of the higher model Onkyos have outputs for "Front Wide". I was wondering what that was but now I see it's an alternative DTS-HD setup. I'm curious how any of those alternates would work, since movies aren't encoded that way.

The "Front Wide" and "Front Height" are for the new 9.1 Dolby Height Channels and for Audyssey DSX, which is either wide or height channels. They are "matrixed" channels from the L and R channels. IOW, they're not "discrete" channels recorded on the disc... they're "extracted" from the L/R channels.

Craig

The older rec was for 90 degrees to the listening position, and still is valid for dipoles. For bipoles and monopoles, 100 to 110 degrees is the newer rec.

Craig

That should be fine. I believe your surrounds are monopoles, so you should try to aim them towards the listening position. That mount should allow you to do so.

Craig

Based on a select-from-20-speaker Digital Cinema standard called SMPTE 429M, Dolby, DTS, and Blu-Ray came up with a 7.1 channel concept that would allow BD content providers to mix audio in several new 7.1 speaker configurations. A touch of 'magic' in the Dolby or DTS decoder would remap the 6.1/7.1 content decoded from the BD into any other 6.1/7.1 speaker layout the homeowner had in place. Several problems ensued: (1) the content providers basically stuck with 5.1, and a few (re)mixes into the 6.1 and 7.1 standard configurations, (2) the consumers (mostly) didn't understand it or want speaker layouts other than 6.1 or 7.1 standard, and (most importantly) (3) the receiver manufacturers did not support remapping into speaker configurations other than 6.1, or 7.1 standard.

Dolby seems to have said very little about the whole process (and, in any event, there are only a few 7.1 TrueHD BDs), but DTS made it something of a centerpiece in their DTS-HDMA advertising...

As always, things might be different next year...

[In any event, we will probably get the chance to be confused again, about (10.1 to) 22.2 channel audio speaker layouts related to 4th generation optical storage for movies/tv, in 7 to 10 years...?! ]

From a rookie - thanks for the links - this helps

You can sit 11' from a 100" diagonal screen and have no problems watching as many DVDs in a row as you care to. That's about 36 degrees and matches the THX recommended viewing angle for the farthest seat in the theater from a scope screen.

You can move up to 9' and watch good scope transfers for hours on end.

If 2010 really brings 2K line screens with good line-doublers/interpolators to home tv sets, we 'should be' looking at a different set of seating distance from screen numbers - more like those for Digital Cinema displays......