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I am contemplating building a room based on 6.1 vs 7.1 and I was wondering if I anyone thinks this is a bad idea? There are two reasons to do this, the first is the location of the door, and since it is cut out of part my foundation I cannot change it. The door is located in the location that the right rear surround would ideally be located, so the only way I could do 7.1 would be to have the speakers either really far apart, close to the side wall, or really close together centered in the room, which really isn't all that different than 6.1. My second reason is I am doing matching bookshelves all around. These bookshelves are sold only as pairs, so I can either get 6 or 8. 6 is obviously cheaper, and 8 leaves a wasted speaker.


I know there are not of ton of true 7.1 soundtracks, so I am not too worrried about missing too much, but I am worried about the effect 6.1 can have on the accoustics where sometimes with a single rear, it can sound like the sound is coming from the front instead of back. Is there any way to mitigate that?


Room dimensions are 23x17x8


Thanks



PS, I know I can always wire for both scenarios, and I will do that just in case, I am just looking for other feedback
 

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Quote:
Originally Posted by davdev  /t/1471879/would-i-regret-going-6-1-vs-7-1#post_23292829


I am contemplating building a room based on 6.1 vs 7.1 and I was wondering if I anyone thinks this is a bad idea?
Depends on where your main seating is located: at or near the back wall, then stick to a 5.1 layout; well away from the back wall, then 7.1 will work.
Quote:
Originally Posted by davdev  /t/1471879/would-i-regret-going-6-1-vs-7-1#post_23292829


...the only way I could do 7.1 would be to have the speakers either really far apart, close to the side wall...
If your seating is at least 7.5 feet away from the back wall, then your rear speakers would not be too far apart (near the side walls would mean a 90 degree spread).
Quote:
Originally Posted by davdev  /t/1471879/would-i-regret-going-6-1-vs-7-1#post_23292829


I know there are not of ton of true 7.1 soundtracks...
There are over 700 Blu-rays with discrete 7.1 soundtracks. Besides, 5.1 material plays really well on 7.1 speakers.
 

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I'd go 7.1 personally. The amount of content is increasing quickly, and as Sdurani mentioned there is already a lot of content in 7.1 That will soon become the main mix on the majority of BR content.
 

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I opted to go 6.1 instead of 7.1...I did however wire for 11.1. Like Carbo said above i used in ceiling for my surrounds. My room is similar in size to yours except I have 10ft ceilings. I used Mirage OmniCans, miragespeakers.com/products/omnican-series/?sku=OMNICAN-OC-65 for my surrounds. The dispersion of sound was so good for my environment that I only chose to stay at 6.1...sounds like 11.1.
 

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I am facing the same situation. Will wire for 7.1, but will probably only do 6.1. Here are my reasons:


1) THX recommends putting the 2 rear speakers right beside each other... um, in other words, they basically RECOMMEND 6.1 over 7.1.


2) Audyessy says their studies show it is more important to add wide and height speakers before adding a 2nd rear speaker (in other words 1 rear is enough!)


3) to avoid the issue of the 1 rear sounding like it is coming form the front (which frankly, I'm not too worried about), just tilt is downward toward your seating position so it's not firing directly at the opposite wall. Easy fix.


4) no sense burdening my multi-channel amp unnecessarily... leaves more power for all other speakers


5) even though the number of movies with discrete 7.1 channels of audio in steadily increasing and one day they may all come with 7.1, realistically how often will it matter if the rears are in mono v.s. stereo... I'm guessing hardly ever.
 

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Quote:
Originally Posted by stereoforsale  /t/1471879/would-i-regret-going-6-1-vs-7-1#post_23714593


1) THX recommends putting the 2 rear speakers right beside each other... um, in other words, they basically RECOMMEND 6.1 over 7.1.
Um, for lossless audio (Dolby TrueHD and DTS-HD MA), they recommend spreading the rear speakers 60 degrees apart:




Check it out for yourself:
http://www.thx.com/consumer/home-entertainment/home-theater/surround-sound-speaker-set-up/
Quote:
Originally Posted by stereoforsale  /t/1471879/would-i-regret-going-6-1-vs-7-1#post_23714593


2) Audyessy says their studies show it is more important to add wide and height speakers before adding a 2nd rear speaker (in other words 1 rear is enough!)
The studies they point to show that our human hearing is weaker around us than in front of us (duh). They twist this into a 9-speaker recommendation that places a full 7 of those speakers up front and uses only 2 speakers to cover the entire surround field. Talk about lopsided. Placing more speakers where our hearing is strongest makes as much sense as prescribing eyeglasses for people with the strongest vision or giving crutches to people with the strongest legs.


Thankfully, the movie industry has done the exact opposite of Audyssey's recommendations, going from one surround channel (Dolby Stereo) to 2 surround channels (discrete 5.1) to 3 surround channels (Surround EX) to 4 surround channels (discrete 7.1). Meanwhile, the number of front channels has stayed the same (3) during all those years. So, they've added channels where our human hearing is weakest and needs the additional support.
Quote:
Originally Posted by stereoforsale  /t/1471879/would-i-regret-going-6-1-vs-7-1#post_23714593


3) to avoid the issue of the 1 rear sounding like it is coming form the front (which frankly, I'm not too worried about), just tilt is downward toward your seating position so it's not firing directly at the opposite wall. Easy fix.
The psychoacoustic phenomenon of imaging reversals is not caused by reflections off the front wall, so you can't fix the problem by tilting the rear speaker down, since you'll still hear the sound exactly the same in both ears, just as you would if the sound were directly in front of you (which is where you brain will reflexively place it momentarily).


Truly fixing the problem couldn't be easier: just use 2 rear speakers, spread well away (at least 60 degrees) from the listener's centre line. When Dolby, DTS and THX were coming up with EX/ES formats, they all recommended playing back the mono surround-back channel through 2 speakers. It was the only channel where 2 speakers were recommended for playback. So, you might not be "too worried about it", but clearly the people that invented 6.1 technology rightfully were.
Quote:
Originally Posted by stereoforsale  /t/1471879/would-i-regret-going-6-1-vs-7-1#post_23714593


4) no sense burdening my multi-channel amp unnecessarily... leaves more power for all other speakers
If your 7-channel amp is burdened by 7 speakers, you need a better amp.
Quote:
Originally Posted by stereoforsale  /t/1471879/would-i-regret-going-6-1-vs-7-1#post_23714593


5) even though the number of movies with discrete 7.1 channels of audio in steadily increasing and one day they may all come with 7.1, realistically how often will it matter if the rears are in mono v.s. stereo... I'm guessing hardly ever.
Only if you can't hear the difference between sounds over your left shoulder vs sounds over your right shoulder.
 

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thanks sdurani. I appreciate your comments. Problem I have is there is still a debate and no conclusive agreement, which you seem to confirm. This is why I think 6.1 is just fine, if 7.1 isn't a realistic or convenient option (which I think was the point of this thread). Of course, if time, space and money are no object, then get 11 speakers, 5 subs and a 1000W x 11ch amp. Specifically addressing the points above:


1) THX recommends different placement of the rears depensing on the mode/usage - i.e. no consensus.


2) Audyssey and the industry disagree - i.e. no consensus. And I disagree with your analogy re: glasses. A better analogy would be: 2 rear speakers is like giving glasses to a blind man, whereas adding speakers to the front is like giving binoculars to a person with 20/20 vision.


3) not an easy fix if you have a door where the one of the 2 rears is supposed to be. Living with the psychoacoustic phenomenon might just be one of those trade-offs in life. I can think of worse things in life.


4) I agree. Given space constraints I have to make due with what I have... and I'd rather give some more headroom to my mains than add a 7th speaker right now... may change when I do my next upgrade.


5) On this point, I'm not sure. I was led to believe the reason for using 2 rear speakers is to eliminate the psychoacoustic phenomenon you mentioned eariler. The 2 rear speakers working together will place the sound as if it is coming from right behind you (not over your left and right shoulder as you suggest), in the same way your L & R speakers image a sound precisely between them (which, btw, is an arguement that you don't really need a centre channel either). And it is worth mentioning this rear stereo effect will only be felt by the person sitting in the sweet spot - all other listeners will not get a well defined central rear sound with 7.1 (but they would with 6.1 - which is another potential reason 6.1 is actually better than 7.1... so it may be that 7.1 also presents it's own trade-offs).


In any event, I don't disagree with your general point. I'm just saying that there are arguments both ways, and no consensus, so no worries if you do 6.1 if you need to. I will say the jump form 5.1 to 6.1 is signficant (if your rear walls are far behind the sitting area), but perhaps the jump from 6.1 to 7.1 is not as big. Some may disagree, hence no consensus.
 

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As others have mentioned, 7.1 in the ceiling sounds like a good solution based on your constraints. I'd wire for that in case you don't like the 6.1 experiment.
 

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Quote:
Originally Posted by Spaceman  /t/1471879/would-i-regret-going-6-1-vs-7-1#post_23716199


As others have mentioned, 7.1 in the ceiling sounds like a good solution based on your constraints. I'd wire for that in case you don't like the 6.1 experiment.

Just curious, would in-ceiling speakers be effective if they are several feet (12-17ft) behind the seating area?
 

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Quote:
Originally Posted by sdurani  /t/1471879/would-i-regret-going-6-1-vs-7-1#post_23715442


Um, for lossless audio (Dolby TrueHD and DTS-HD MA), they recommend spreading the rear speakers 60 degrees apart:




Check it out for yourself:
http://www.thx.com/consumer/home-entertainment/home-theater/surround-sound-speaker-set-up/

The studies they point to show that our human hearing is weaker around us than in front of us (duh). They twist this into a 9-speaker recommendation that places a full 7 of those speakers up front and uses only 2 speakers to cover the entire surround field. Talk about lopsided. Placing more speakers where our hearing is strongest makes as much sense as prescribing eyeglasses for people with the strongest vision or giving crutches to people with the strongest legs.


Thankfully, the movie industry has done the exact opposite of Audyssey's recommendations, going from one surround channel (Dolby Stereo) to 2 surround channels (discrete 5.1) to 3 surround channels (Surround EX) to 4 surround channels (discrete 7.1). Meanwhile, the number of front channels has stayed the same (3) during all those years. So, they've added channels where our human hearing is weakest and needs the additional support.

The psychoacoustic phenomenon of imaging reversals is not caused by reflections off the front wall, so you can't fix the problem by tilting the rear speaker down, since you'll still hear the sound exactly the same in both ears, just as you would if the sound were directly in front of you (which is where you brain will reflexively place it momentarily).


Truly fixing the problem couldn't be easier: just use 2 rear speakers, spread well away (at least 60 degrees) from the listener's centre line. When Dolby, DTS and THX were coming up with EX/ES formats, they all recommended playing back the mono surround-back channel through 2 speakers. It was the only channel where 2 speakers were recommended for playback. So, you might not be "too worried about it", but clearly the people that invented 6.1 technology rightfully were.

If your 7-channel amp is burdened by 7 speakers, you need a better amp.

Only if you can't hear the difference between sounds over your left shoulder vs sounds over your right shoulder.
+1


I have gone from 5.1 > 5.1+DSX Wide > 7.1

IMO, the rear surrounds are much better than the problematic DSX Wide.
 

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Quote:
Originally Posted by stereoforsale  /t/1471879/would-i-regret-going-6-1-vs-7-1#post_23716605


Just curious, would in-ceiling speakers be effective if they are several feet (12-17ft) behind the seating area?

Do they have to be that far back? What would keep you from placing them closer?


Triad offers a few options with angled baffles. I think 60 degrees above/behind the listening position is the recommended placement but you would need to confirm that.
 

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Quote:
Originally Posted by Spaceman  /t/1471879/would-i-regret-going-6-1-vs-7-1#post_23717022


Do they have to be that far back? What would keep you from placing them closer?


Triad offers a few options with angled baffles. I think 60 degrees above/behind the listening position is the recommended placement but you would need to confirm that.

I have a bulk head running just behind the sitting area, and then a ~15 ft open space past that. I thought about putting rears along the bulk head, but it would be too close to the seating area for decent effect. I figure I'd need to put in-ceiling speakers several feet behind the bulk head so that the sound isn't blocked. So, for now, I've been doing 6.1 (1 rear against the back wall) and this is a major improvement over 5.1. Unfortunately, it's not as easy to add 2 rear speakers as some people like to suggest. Given the dimensions of my room, there is virtually no way to position 2 rears 60 degrees apart without them behind blocked by other walls.


Another reason I'm doing 6.1 is my 6th speaker matches my 5 other speakers. Even if I wanted to buy a 7th, they are discontinued. I'd rather use this 1 amazing speaker and keep the tonal balance thru-out the room, rather than buy a pair of inferior mis-matched speakers.


At the end of the day, unless someone can confirm that the 2 rears are primarily designed to do more than create a single image coming from behind listener, then I'm inclinded to think a well positioned 6.1 set up (even with the psychoacoustic phenomenon) is superior to a poorly positioned and mis-matched 7.1 set up.


And it may also be worth mentioning that the original studies found the ideal surround sound is achieved with only 5 channels - with the 5th channel being 1 rear, not the center channel. But why sell 5 speakers when you can convince people to buy 7, 9 even 11 speakers! Heck now they are telling us to buy 4 subs! Anyway you get my point
 

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Quote:
Originally Posted by stereoforsale  /t/1471879/would-i-regret-going-6-1-vs-7-1#post_23716159


1) THX recommends different placement of the rears depensing on the mode/usage - i.e. no consensus.
They recommend rear speakers 60 degrees apart when listening to lossless soundtracks, which is all you'll be listening to on Blu-ray. Interesting that you point to their speaker-together recommendation earlier but, just one post later, dismiss their speaker-apart recommendation because it doesn't fit with your pre-determined decision.


THX doesn't validate a 6.1 placement: even with the rear speakers together, they use ASA (spatializer-like processing) to make the rear speaker sound like they're further apart, which cannot be done with a single speaker. Considering their speaker-apart recommendation is the same as Dolby and DTS recommendations, there most definitely is concensus.
Quote:
Originally Posted by stereoforsale  /t/1471879/would-i-regret-going-6-1-vs-7-1#post_23716159


2) Audyssey and the industry disagree - i.e. no consensus. And I disagree with your analogy re: glasses. A better analogy would be: 2 rear speakers is like giving glasses to a blind man, whereas adding speakers to the front is like giving binoculars to a person with 20/20 vision.
Again, there is concensus; Audyssey is the outlier, since they sell processing that generates heights and wides (and don't sell processing to extract rears). And, as with THX, there is nothing on the Audyssey website validating a 6.1-speaker set-up.


BTW, my analogy had to do with Audyssey adding support where our hearing is already at its best rather than supporting where our hearing is weaker, as everyone else in the industry (commercial cinema AND consumer audio) has done. You blind man analogy would work if were were deaf to the surround field, which is hardly the case.
Quote:
Originally Posted by stereoforsale  /t/1471879/would-i-regret-going-6-1-vs-7-1#post_23716159


3) not an easy fix if you have a door where the one of the 2 rears is supposed to be. Living with the psychoacoustic phenomenon might just be one of those trade-offs in life. I can think of worse things in life.
You could say that about anything. Heck, there are worse things in life than not having a home audio set-up.


Rear speaker placement doesn't have to be exactly 60 degrees apart, just away from the centre line. So the door can be worked around, though that isn't the real reason you're avoiding 7.1.
Quote:
Originally Posted by stereoforsale  /t/1471879/would-i-regret-going-6-1-vs-7-1#post_23716159


4) I agree. Given space constraints I have to make due with what I have... and I'd rather give some more headroom to my mains than add a 7th speaker right now... may change when I do my next upgrade.
Not using one out of 7 outputs will give a negligible amount of headroom to the other 6 speakers. Again, that's not the reason you're avoiding 7.1.
Quote:
Originally Posted by stereoforsale  /t/1471879/would-i-regret-going-6-1-vs-7-1#post_23716159


5) On this point, I'm not sure. I was led to believe the reason for using 2 rear speakers is to eliminate the psychoacoustic phenomenon you mentioned eariler. The 2 rear speakers working together will place the sound as if it is coming from right behind you (not over your left and right shoulder as you suggest), in the same way your L & R speakers image a sound precisely between them (which, btw, is an arguement that you don't really need a centre channel either). And it is worth mentioning this rear stereo effect will only be felt by the person sitting in the sweet spot - all other listeners will not get a well defined central rear sound with 7.1 (but they would with 6.1 - which is another potential reason 6.1 is actually better than 7.1... so it may be that 7.1 also presents it's own trade-offs).
Your explanation is based on a false premise, since that's not how two speakers work, even when generating the same signal. The sound from each speaker is heard in the nearby ear first, then (after a brief inter-aural delay as some of the frequencies wrap around your head) the sound is heard the opposite ear. This is very different from a single speaker, where the sound shoots directly to both ears.


This is why Dolby, DTS and THX all recommended two speakers for reproducing a mono surround-back signal. They wouldn't have done this if there was no difference betwen using a single rear speaker and 2 rear speakers.
Quote:
Originally Posted by stereoforsale  /t/1471879/would-i-regret-going-6-1-vs-7-1#post_23716159


In any event, I don't disagree with your general point. I'm just saying that there are arguments both ways, and no consensus, so no worries if you do 6.1 if you need to. I will say the jump form 5.1 to 6.1 is signficant (if your rear walls are far behind the sitting area), but perhaps the jump from 6.1 to 7.1 is not as big. Some may disagree, hence no consensus.
There is plenty of concensus, but it doesn't fit in with your a priori decision to use a single rear speaker. If you want to do a 6.1 layout (because you can't find a 7th speaker of your discontinued model), then that's your prerogative. The validation you're desperately looking for doesn't exist.
 

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Ok, thanks for the info. Yes, 7.1 is the way to go. Given my constraints, any recommendation how I can achieve it? Specifically:

1) what in the minimum degree separation between the 2 rears you recommend?

2) is it ok if the rears are actually further apart than the surrounds?

3) would it be ok to use different speakers in the rear? I'm not really in the market to buy a whole new set.

4) is there any concern that the rears will be significantly further away than my other speakers and therefore set to a much higher volume? Will the typical wall small mount speakers be adequate? Or is this much ado about nothing?
 

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Quote:
Originally Posted by stereoforsale  /t/1471879/would-i-regret-going-6-1-vs-7-1#post_23718251


1) what in the minimum degree separation between the 2 rears you recommend?
At least 60 degrees. If there is a door at 30 degrees from the centre line, then spread your rear speakers wider to avoid the door.
Quote:
Originally Posted by stereoforsale  /t/1471879/would-i-regret-going-6-1-vs-7-1#post_23718251


2) is it ok if the rears are actually further apart than the surrounds?
Physical distance isn't the issue, speaker angle is. If avoiding the door means that your rear speakers are 70 or 80 degrees apart, then that's not a problem. By comparison, your side speakers should be directly to your sides, which places them 180 degrees apart. Your rears won't even come close to that spread (angular spread, not physical distance).
Quote:
Originally Posted by stereoforsale  /t/1471879/would-i-regret-going-6-1-vs-7-1#post_23718251


3) would it be ok to use different speakers in the rear? I'm not really in the market to buy a whole new set.
Yes. Even in this day and age of surround sound, the front soundstage remains critical. So, matching L/C/R speakers is most important. The surrounds aren't as critical because they play back less content AND the content they are playing back isn't as important to following the story (mixers don't put important dialogue in the surround channels).


With that in mind, the speakers at your sides have to blend in with the front soundstage in order to bring the sound into the room. So having identical (or tiimbre matched) sides is helpful. Less important are the rear speakers, since they are further away from the soundstage (not to mention that our human hearing is not as acute behind us).


BTW, I would still keep an eye out on eBay and AudioGon and other sites to see if a used pair of your current speakers show up. Down the road, if you can replace your rears with speakers that are identical to the others, then that would be nice.
Quote:
Originally Posted by stereoforsale  /t/1471879/would-i-regret-going-6-1-vs-7-1#post_23718251


4) is there any concern that the rears will be significantly further away than my other speakers and therefore set to a much higher volume? Will the typical wall small mount speakers be adequate? Or is this much ado about nothing?
Small wall-mount speakers from the same brand as your current speakers would be a good choice. The difference in level needed for their further placement won't blow them up (not like your're putting them 30 feet further than your other speakers).
 

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Quote:
Originally Posted by sdurani  /t/1471879/would-i-regret-going-6-1-vs-7-1#post_23718401


At least 60 degrees. If there is a door at 30 degrees from the centre line, then spread your rear speakers wider to avoid the door.

Physical distance isn't the issue, speaker angle is. If avoiding the door means that your rear speakers are 70 or 80 degrees apart, then that's not a problem. By comparison, your side speakers should be directly to your sides, which places them 180 degrees apart. Your rears won't even come close to that spread (angular spread, not physical distance).

Yes. Even in this day and age of surround sound, the front soundstage remains critical. So, matching L/C/R speakers is most important. The surrounds aren't as critical because they play back less content AND the content they are playing back isn't as important to following the story (mixers don't put important dialogue in the surround channels).


With that in mind, the speakers at your sides have to blend in with the front soundstage in order to bring the sound into the room. So having identical (or tiimbre matched) sides is helpful. Less important are the rear speakers, since they are further away from the soundstage (not to mention that our human hearing is not as acute behind us).


BTW, I would still keep an eye out on eBay and AudioGon and other sites to see if a used pair of your current speakers show up. Down the road, if you can replace your rears with speakers that are identical to the others, then that would be nice.

Small wall-mount speakers from the same brand as your current speakers would be a good choice. The difference in level needed for their further placement won't blow them up (not like your're putting them 30 feet further than your other speakers).

Thanks for the thoughtful response. I think you see that I wasn't trying to desperately advocate my point. I was open to your more-informed opinion (even if a bit sarcastic
). As for finding a matching 7th channel, I've been looking online all summer... but even the 1 rear I have now is rather large and heavy for a "rear" so it will probably be easier to get 2 new smaller ones, even if they are not the same as all the others. Your comments reassure me that timber matching is not an issue for the rears. I'm using B&W Matrix series so I'm thinking a pair of B&W M1s or FPM-2s will do the trick for the surrounds... I hope I don't blow the up! (maybe I'll buy used just in case
 
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