How Critical do you feel the standard Speaker Placement Angles are (i.e. ITU standards, THX, etc.)

Matthew J Poes

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I'm sure all of you have heard about the standards for surround speaker placement. The notion comes from a set of standards derived and adopted by the ITU in the monitoring and mastering of surround recordings. These standards were then translated for home use by groups like THX, Dolby, etc. In fact, I believe THX may have started the notion of an industry standard before the ITU ever adopted anything.

In any case, the issue then becomes, how critical are those angles in your opinion. I fully understand the conceptual reason for having and following them. However we also know that in the real world most people cannot adopt those angles precisely. Do you have any direct experience with this? Ever had a system go from being out of compliance to within compliance and find that the move alone made for a huge difference.

Fig_2_ITU51.gif

My own experience is a sort of mixed bag in this regard. I have found that the surround location is fairly critical to get proper envelopment, but have also found that raising the surrounds above head level is often preferable for me. Having tried both at ear level and above I have found it preferable to raise the elevation some.

For the fronts, the angle can be 22 degrees (narrower placement) to 30 degrees, standard ITU placement. This does not change as channels are added and is consistent across recommendations. Many are strong adherents to this set of angles., feeling that a deviation causes a loss in the continuity of the sound stage. One thought I have had is that most theaters have many times more speakers than the mastering setup would have (not to say they don't "check" the final master in a real theater) and so the intended final location isn't a match to the mastering studio, yet is ok.

Do your speakers currently meet the ITU standards? If not, which speakers are off? What do you think about that?
 
Interesting topic and I completely agree with your comment about "real world."

My multichannel placements aren't exact to spec (due to real world) and I definitely prefer my side and rear surrounds to be slightly elevated (I might feel differently in a significantly larger room... but in my space that's my preference not to mention a necessity). That elevation is slightly problematic for Atmos, but I think I found a happy medium. And my rear channels are slightly shifted to the left.

Frankly, I think my room sounds great... so strict standards get kicked to the curb!
 
I also agree that the standards dont mean much in the home. With all the flavors of auto room EQ once the system has been run through its process it sounds better than most theaters Ive been in. Of course placement of speakers makes a difference but if your close to where they need to go you'll be fine.
 
I too wonder about the science behind the standards. Which is not to suggest I know anything about what went into them. What I had always understood was that the goal was to create a common standard to be used by studios and homes which match. That if we follow this placement standard we will recreate what the engineers intended.

I toured one surround music mastering studio and two multipurpose studios that mostly did movies or TV shows. The music studio matched the iTunes standard in a lot of ways, but was honestly nothing special. In fact they mixed up to 7.1 music tracks but only had 5.1 speakers, which made little sense to me. They relied on software and some final QC (taking it home to listen) to ensure the back channels mixed ok (and argued it was no big deal because few musicians wanted the back channels anyway).

The first movie sound studio was basically a small theater. The space could seat maybe 50-75 people. The front had 5 speakers left to right. Surrounds extended from maybe 6 feet back from the front screen wall all the way to the back and wrapping around the seating. I forget how many but certainly more than 10 surround effects speakers. Height speakers were in 4's across the ceiling and I believe there were 6 rows front to back. They had far more speakers than the ITU standard and the angles would not have matched for them. How does that then translate into what is right for my setup? They localizabilty of speakers and continuity of soundstage is very room acoustic dependent which makes me think there is more to it than the ITU circle would allow for.
 
The the ITU circle also only benefits the one listening position and dose not work well for a room with multiple seating positions.
 
Also have the sides and rears above ear height. About 18". It just seems to make sense unless you a) don't have a high backed chair to block the sound or b) never have anyone sitting to your sides. Also FWIW SVS has guidance in their speaker owners manuals for sides and rears for tweeter 2ft above ear level along with the ITU and Dolby placement diagrams.
 
Would any of you be willing to share your front speaker distance to the primary listening position and distance apart. Basically the necessarily dimensions of the triangle to calculate the angle for the L and R main speakers? I'm really curious where most people fall.
 
I have my mains sitting 11ft from the MLP and they sit 9ft apart
 
I do run a 7.1 speaker configuration and have been pleased with how it sounds. My room is 13ft wide and 27ft long with an 8.5ft height
 
I'm jealous you all have so much more width. I have a staircase and pipes that made it impossible to make the room 13 feet wide. I would have had about 13-14' if not for the staircase.
 
Room is 11 feet wide. Screen is 80inch (6.6ft) wide. Front speakers 7ft 4.5inch apart center to center. Sitting 7ft 7" to front right/left speakers at MLP. 29 degrees.
 
My speaker placement has never met those standards. For starters, I like my front speakers spread further apart than the standard equilateral triangle.

I also prefer the rear speakers elevated. In our previous home they were 7-1/2 feet off the floor and about 2-3 ft. behind the seating. I don’t see any reason why the rear speakers need to be aimed at the seating. If they’re some distance away (7-10 ft. in our place), the natural dispersion will get the highs to the seating. If the speakers are closer in proximity, the highs could always be boosted a bit to compensate for them being slightly off-axis.

The home previous to the one mentioned had the rear speakers directly behind and about 6 ft. from the seating, and about 8 ft. above the floor, angled downward towards the seating. I was happy with the performance in both homes.

Regards,
Wayne
 
i come in right around 23.5 deg
 
Room is 11 feet wide. Screen is 80inch (6.6ft) wide. Front speakers 7ft 4.5inch apart center to center. Sitting 7ft 7" to front right/left speakers at MLP. 29 degrees.

That's near ideal and your room width and screen width nearly match mine. Any chance you have a picture to share. I couldn't fit my mains outside the screen without placing them too close to the side walls.
 
i come in right around 23.5 deg

Looks like most of us are on the narrow side of acceptable.

My last setup had the speakers spread around 30 degrees apart and this one just depends on where you sit. It ranges from 15 degrees in the worst seats to 23 degrees in the best seats. When in the right seats I don't find it to be a problem, it sounds as good as I'm used to. Sitting back on the riser in a fully reclined position does seem to create a narrow collapsed stage but it also isn't all that unnatural. To me at least, it isn't night and day. The stage shrinks but so does the screen since the viewing cone goes from 36 to 25 degrees.

I can really see why people go for those full wall screens. In my setup that would actually provide enough speaker placement flexibility to better meet these ITU standards over a wider range of seating distances and the screen viewing cone would better match the THX standard. The problem for me is that this would be about a 130-140 inch (diagonal) screen, which my projector could not light up bright enough to meet my needs.
 
That's near ideal and your room width and screen width nearly match mine. Any chance you have a picture to share. I couldn't fit my mains outside the screen without placing them too close to the side walls.
It worked out that way by accident.
Currently using A2.4s on stands. Center of woofer 32" from front wall and 22" from side wall. Speakers are toed in to cross about a foot in front of MLP. Also by accident this has them aiming at the rear corner traps in the rear corners of this 11'W x 12.5'L x 10'H room.
For the space and screen size this is the best set-up I've found.
IMG_1324.JPG IMG_1325.JPG
 
It worked out that way by accident.
Currently using A2.4s on stands. Center of woofer 32" from front wall and 22" from side wall. Speakers are toed in to cross about a foot in front of MLP. Also by accident this has them aiming at the rear corner traps in the rear corners of this 11'W x 12.5'L x 10'H room.
For the space and screen size this is the best set-up I've found.
View attachment 6816 View attachment 6817

I'm going to have to take some measurements now to see where that same placement would put my speakers. When I designed the room the optimal placement for the speakers ended up being where the screen frame is or near it. It would have been ok to place them outside the screen but it placed them just inches from the side walls, not 22". My speakers are much wider so that does create some placement constrictions.

P.s. can you tell in looking at widening the speakers! I've been itching to try it for a while but there seems like no good place to put them.
 
I firmly believe placement and angle of toe-in are significantly dependent on the speaker, your room, your listening position and whether you have the capability to properly frequency match your speakers.

I would nearly always start with the Cardas recommendation and depending on the other factors, move your two main front speakers from there... only a few inches at a time, trying various toe-in angles... with the proper music to test such. Provided you are a music listener, first and foremost get your front mains setup for the best you can for music... and the movies will sound really good as well, at least in every instance I've heard they have. If you have good imaging, sound stage width and depth (acuity), which will nearly always hinge on placement and frequency matching your two primary speakers, your movies will sound phenomenal as well, particularly when you add in your center.

I've had better luck with rears being in the rear corners and just slightly above my ears when sitting in my main listening position.... especially now that I have four height speakers with Atmos. I also like the rears in this location for SACD... as too high up just doesn't get it for me.

And humbug on moving the measurement mic to other seats. I am typically the only one in the room. But even if someone is visiting (outside of maybe the guys during our speaker evaluations)... the others could care less about their seat being optimized. They could lie on the floor or hang from the ceiling and they'd think it sounds great. I ALWAYS optimize for my main listening position and NO other seats. Measuring those other seats is only going to mess up my main listening position and get the front main speakers out of frequency balance... and it won't improve those other seats enough to justify messing with my prime listening position. About 99.5 percent of the time... I am the ONLY one who cares... most others would never know the difference, as their jaw is dropped to the floor as it is.
 
I firmly believe placement and angle of toe-in are significantly dependent on the speaker, your room, your listening position and whether you have the capability to properly frequency match your speakers.

I would nearly always start with the Cardas recommendation and depending on the other factors, move your two main front speakers from there... only a few inches at a time, trying various toe-in angles... with the proper music to test such. Provided you are a music listener, first and foremost get your front mains setup for the best you can for music... and the movies will sound really good as well, at least in every instance I've heard they have. If you have good imaging, sound stage width and depth (acuity), which will nearly always hinge on placement and frequency matching your two primary speakers, your movies will sound phenomenal as well, particularly when you add in your center.

I've had better luck with rears being in the rear corners and just slightly above my ears when sitting in my main listening position.... especially now that I have four height speakers with Atmos. I also like the rears in this location for SACD... as too high up just doesn't get it for me.

And humbug on moving the measurement mic to other seats. I am typically the only one in the room. But even if someone is visiting (outside of maybe the guys during our speaker evaluations)... the others could care less about their seat being optimized. They could lie on the floor or hang from the ceiling and they'd think it sounds great. I ALWAYS optimize for my main listening position and NO other seats. Measuring those other seats is only going to mess up my main listening position and get the front main speakers out of frequency balance... and it won't improve those other seats enough to justify messing with my prime listening position. About 99.5 percent of the time... I am the ONLY one who cares... most others would never know the difference, as their jaw is dropped to the floor as it is.

Well of course. This shouldn't be about other people. It's my theater. My opinion matters most.
 
I think some get a bit caught up in trying to get every seat optimized not realizing how little most others around them will care. If we are trying to optimize for several seating locations... we may as well forget about two-channel in that system and use it for movies only. I remember when I was helping SVS with customer support, I spent most all day helping people figure out why their bass didn't sound any better than it did... and most of it was because they tried to optimize for 2 to 8 seats all over their room. I would ask them to optimize for their primary seating location only and their response was "wow... what a difference" every time. Then I would say... "Now it's your choice which way you want to set it up." Naturally they would leave it at the one seat setup.
 
I think some get a bit caught up in trying to get every seat optimized not realizing how little most others around them will care. If we are trying to optimize for several seating locations... we may as well forget about two-channel in that system and use it for movies only.

Or a processor that can keep 2 configurations. One just for us and one just in case we find a friend to watch with :)
Also anyone proficient with REW and having multiple subs should really give MSO (Multi-Sub Optimizer) a try if they haven't already.

I firmly believe placement and angle of toe-in are significantly dependent on the speaker, your room, your listening position and whether you have the capability to properly frequency match your speakers.

To add to this, I remember reading a speaker review by AudiocRaver some time ago where he remarked the speakers imaged best when the distance to each from the MLP was within 1/4" or less. When I first read it I thought that's crazy, how can there be a significant difference between 1/2" and 1/4"? Then I tried it. There is a difference and the reward for precision here is worth the time. (Thanks for the education!) And for toe-in, using a laser and painters tape on a wall or sofa back is the best way I've found to make sure they match.
 
Yep... that is one thing nice about having the miniDSP DDRC... it has four presets that can easily be switched. However, I tried it both ways and I can't tell a difference in the other seats between the two... neither is going to be perfect.

People spend a lot of money on speakers to not be able to place them to get their best sound. Placement is so very critical if you want the best music sound... not so much for movies.
 
I think some get a bit caught up in trying to get every seat optimized not realizing how little most others around them will care. If we are trying to optimize for several seating locations... we may as well forget about two-channel in that system and use it for movies only. I remember when I was helping SVS with customer support, I spent most all day helping people figure out why their bass didn't sound any better than it did... and most of it was because they tried to optimize for 2 to 8 seats all over their room. I would ask them to optimize for their primary seating location only and their response was "wow... what a difference" every time. Then I would say... "Now it's your choice which way you want to set it up." Naturally they would leave it at the one seat setup.

When I ran Dirac in my last HT, I ran it for the single seat. I tried running it at the whole couch, but I found it just didn't sound as good to me or my friends when they auditioned it. The other advantage to doing a close Mic setup was I was able to place my Mic in exactly the same spot every time. This way if I made a change to the system I could run it again, and compare changes to the system to what it showed graphically, and how it changed the sound.
 
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