Going to 7.1-Channel Surround Sound

[admin]

Almost everyone loves surround sound, (except for an eccentric actor whom I know who actually prefers mono!) and what’s not to love? Our ears are on each side of our head, canted forward, but we hear sounds from every direction with almost equal precision. For that reason multi-channel sound reproduction is intrinsically more realistic and believable. But how many surround speakers are required to present a plausible illusion of the real thing?

Discuss "Going to 7.1-Channel Surround Sound" here. Read the article.

 

[RF2000]

Nice ad

for Axiom audio. The amount of people using more than 5.1 right now is miniscule, good luck selling more speakers.

 

[Lordoftherings]

Old DD 7.1-channel vs. New Audyssey DSX 9.3-channel.

This is all deja vu all over again.

About DSX and the front immersion? Seems to be more important than the rear surrounds, according to Chris from Audyssey anyway, which I'm really tempted to believe more. That's my next project anyway. Not Dolby Digital Pro Logic IIz, but Audyssey DSX (Dynamic Surround Expansion) from the front soundstage with 5 speakers up front and only 2 in the side/mid-rear, or perhaps 4 (2 on the side and 2 in the rear, we'll see).
Oh ya, with three subs too. So, a possibility of a 9.3-channel system perhaps.
Denon AVR-4310ci and AVR-4810ci anyone?

Ya, I need something fresh and new.

 

[bandphan]

Once channels are discrete and not matrixed, and the room warrants, then yes I can see more moving towards it.

 

[Lordoftherings]

Almost everyone loves surround sound,

That's a fact.

 

[gene]

I do prefer 7.1 (with surround backs) over 5.1 for one very good reason: PLIIx Music Mode. I think it sounds alot better than ordinary PLII in 5.1.

That being said, I also love front height channels but they are impractical in most rooms especially when your front speakers are already 6ft tall and you only have 8ft ceilings

 

[fredk]

for Axiom audio. The amount of people using more than 5.1 right now is miniscule, good luck selling more speakers.

Thats news to me and most others on the Axiom forums.

Which would you add first Gene, a sub, or rear surrounds?

 

[Lordoftherings]

Speakers' positioning.

About Yamaha two front "Presence" speakers? Recommended height > 6 feet.
Just slightly outside your two front mains. No dipoles here.

* Also, the rear (back) surrounds, Alan Loft says 150 degrees max at the rear! You guys agree with that?

* And THX, remember, they were telling us to use two of them, spaced close together by only a couple of feet or so in the center back! Which would be about 170 degrees or so! And of course the two side surrounds at 90 degrees.
And preferably all dipole surrounds!

I'm curious Gene, where did you positioned your two rear surrounds (angles from 0 degree dead front center) and your two side surrounds? Also, dipole or direct radiating speakers?
Or anyone else?

I would really like to know what angles you guys are using for your four surround speakers.

Cheers,

Bob

 

[westcott]

One requirement for 7.1-channel surround is sufficient space behind your couch and listening area—at least 5 feet or more. If your couch is jammed up against the rear wall or you have a comparatively small room of less than about 2,100 cu. ft. (length x width x height), the addition of two rear surround speakers will not likely add significant improvements in envelopment,

Good point and one of the most overlooked part of most 7.1 setups.

Thanks for the article.

 

[Lordoftherings]

Ok, I got 10 feet behind my couch. My two rear surrounds are dead back center, separated by only two feet (from the outside, and only one foot from the inside).
My two main side surrounds (I use two pairs), are at 100 degrees angle.
And all my speakers are direct radiating.

Good, bad?

 

[Bryce_H]

I understand I am in a minority here, but how do things change with multiple rows of seats? Getting the "correct" degrees for the front row, puts the side surrounds in forward of my second row. Right now this is my arrangement as we (just my wife and I) are the predominate users of our home theater. Would going to 7.1 help for the second row by actually getting some sound behind the second row? I also struggled with the discrepancy between THX and Dobly in their recommendations. Oh, well.

 

[jostenmeat]

I understand I am in a minority here, but how do things change with multiple rows of seats? Getting the "correct" degrees for the front row, puts the side surrounds in forward of my second row. Right now this is my arrangement as we (just my wife and I) are the predominate users of our home theater. Would going to 7.1 help for the second row by actually getting some sound behind the second row? I also struggled with the discrepancy between THX and Dobly in their recommendations. Oh, well.

You could use redundant side surrounds, like theaters do. If you use a receiver, which has preouts, then add an amp for the second pair. Just remember to level match.

I recently switched to bipolar side surrounds for greater coverage, after reading an AH build that recommended it. I believe that there is improvement, but that it's subtle and not as profound as I was hoping.

There's not much you can do, otherwise. With multi-rows, there are a number of decisions that must be made, favoring either a compromise between them, or a preference for a particular row/spot. The rears are a good idea for, well, rear coverage, but of course the effect will be more pronounced for the rear row.

Since it's mostly just you and your wife, I think it's best to set it all up to provide the least compromise for your favorite seat. If you do use rears, and your favorite spot is front/center, when you calibrate the rears for this position, it will run too hot for the rear row. C'est la vie.

 

[Bryce_H]

Thanks - I have bipolars on the side now (Def Tech BPX's). I have considered the redundant side surrounds, but given it is mostly my wife and I could never justify the cost. The rear surrounds would potentially increase the experience for us. However there are so few true 7.1 movies out there and I currently can't decode the new audio formats anyway (Denon 3805), so maybe I will just hold out.

 

[Patrick_Wolf]

How could any audioholic object to having MORE speakers?!

 

[Lordoftherings]

Thanks - I have bipolars on the side now (Def Tech BPX's). I have considered the redundant side surrounds, but given it is mostly my wife and I could never justify the cost. The rear surrounds would potentially increase the experience for us. However there are so few true 7.1 movies out there and I currently can't decode the new audio formats anyway (Denon 3805), so maybe I will just hold out.

Hi Bryce,

Are you connecting the multichannel analog out from your Blu-Ray player to the "Ext. In" of your 3805 receiver? So at least you still benefit from the new high resolution audio codecs (Dolby TrueHD and DTS-HD Master Audio).
* [And don't forget to set your Denon AVR-3805 by adding an extra 10db from
the "Ext. IN Subwoofer Level"; page 40 from your manual.]

Cheers,

Bob

 

[Lordoftherings]

How could any audioholic object to having MORE speakers?!

Sometimes, less is more.

 

[Bryce_H]

My bluray player is a PS3, so no external outs (and I own no games, believe it or not). In terms of the comment:

"How could any audioholic object to having MORE speakers?!"

I don't object to more speakers (in fact more speakers have been on the purchase list for years), but budget/economy/15-month old son/etc./etc/ keep pushing it down the priority list.

Sometime soon, I will likely get a new receiver to incorporate all the new codecs. Right now I am working on building my acoustic panels.

 

[palmharbor]

?????? Questions not answered

I have Rocket towers plus Rocket Center Channel and DynAudio between
the towers on each side of Center Channel speaker and Rocket Bipolar
on the left and right of the sofa. I could add two more in the back as I have
the space but unless I know that there are two more channels in HD I get
from HBO I won't do it as I do not have Blue Ray and have no intention
to get it. The reality is that most movies and tv is people talking to each other.
Which means the center does the vast majority of the work in non-action
films. I have the Emotiva processor and I have an extra Sony power amp
but I am not sure if it would be worth it.

 

[jostenmeat]

I have Rocket towers plus Rocket Center Channel and DynAudio between
the towers on each side of Center Channel speaker and Rocket Bipolar
on the left and right of the sofa. I could add two more in the back as I have
the space but unless I know that there are two more channels in HD I get
from HBO I won't do it as I do not have Blue Ray and have no intention
to get it. The reality is that most movies and tv is people talking to each other.
Which means the center does the vast majority of the work in non-action
films. I have the Emotiva processor and I have an extra Sony power amp
but I am not sure if it would be worth it.

You are already setup to use a Audyssey DSX, namely of the "wide" 7.1 variety.

The only real issue I see is that you are mismatched between the Dyns and Rockets for your front stage.

 

[palmharbor]

Mismatch?

I use a ES Sony stereo amp to run the Dynaudio and a 5 channel power amp
for the others. Again: Most of the audio still comes out of the center b/c dialog is there. I have some German MB Quart C 104's I just got to use in the far rear but they are part of my bedroom surround sound system. I will probably leave the living room H.T. alone for now