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Hashpot
05-06-2007, 05:15 PM
do the surround back speakers do they produce a different sound than the surrounds or are the four speakers just left and right surround . I dont notice any difference from the sb and the surrounds. All the dvds that ive seen are a 5.1 format does that ,mean im just getting the same surround affect from my surround back and surround speakers? I think the only way to get a true 7.1 surround is if you get an HD/bluray player is that correct?

PeruvianSkies
05-06-2007, 06:00 PM
do the surround back speakers do they produce a different sound than the surrounds or are the four speakers just left and right surround . I dont notice any difference from the sb and the surrounds. All the dvds that ive seen are a 5.1 format does that ,mean im just getting the same surround affect from my surround back and surround speakers? I think the only way to get a true 7.1 surround is if you get an HD/bluray player is that correct?


Depends....

Here is the deal, when playing a 5.1 DVD the middle rears (left and right) simply take the left and right surround and matrix the sound with the middle left taking the left surround and the right middle taking the right surround.

Now, when playing a discrete 6.1 disc like the DTS-ES discrete DVD's (ex: GLADIATOR) then the middle surrounds are not the same as the left and right surround because they are a discrete channel that is mixed accordingly. That channel is then spit into a left and right to help keep the back soundfield more 'filled in'.

I used to set things up for 7.1, but have since gone back to 5.1 after realizing that there are so few 6.1 discs and that it's better to just have 2 good surrounds that fill the middle soundstage, espcially since I have a smaller room, but for larger rooms it might be helpful.

Hashpot
05-06-2007, 06:11 PM
so your saying the surround back channels do have a seperate sound but they have a weak surround affect factor,maybe its just my speakers i have the onkyo HT-S790 (htib) the surround speakers are pretty weak so I am considering getting some descent bookshelfs

Rock789
05-06-2007, 06:25 PM
I have bookshelves for my surround backs...
I got them since I do have some movies which are 6.1, however, as PeruvianSkies stated... there are few 6.1 movies and for any 5.1 movie the surround backs are not necessary...

PeruvianSkies
05-06-2007, 08:36 PM
so your saying the surround back channels do have a seperate sound but they have a weak surround affect factor,maybe its just my speakers i have the onkyo HT-S790 (htib) the surround speakers are pretty weak so I am considering getting some descent bookshelfs

There are very few DVD's in DTS ES Discrete (6.1) and NONE are 7.1. Here is a short list of some DTS-ES titles that I can think of off the top of my head:

CHICKEN RUN
THE HAUNTING (remake)
GLADIATOR (not the dir. cut)
BLADE II and BLADE III
FINAL DESTINATION 2
SEVEN
SUSPIRIA
THE OSTERMAN WEEKEND
RUSH HOUR 2
X3
DAY OF THE DEAD
NIGHTMARE ON ELM STREET (reissue)
a bunch of the Anchor Bay horror films...

These discs really play well in a 6.1 configuration as there is information that is mixed specifically for that center rear channel. Ex: in Gladiator in the early battle scene I can recall the arrows flying directly from center rear over your head and matching with front center, which sounded great. At the time that I had a 7.1 setup I had a much wider room and therefore the surrounds were much further apart...the surround left and right were about 16 ft apart, so it was nice having a middle rear at the 8ft. halfway point to fill that space. Having 7.1 is very similar to 6.1 except it enables you to have another speaker in order to separate the signal a bit more and I noticed this worked better for 5.1 mixes because it allowed you to essentially have 2 surround rights and 2 surround lefts, which again helps for wider soundstage in the back on larger rooms.

kexodusc
05-07-2007, 03:52 AM
The key here is how the surround processors determine what to send to the rear surrounds vs the side surrounds. They're pretty good at it. In a standard 5.1 signal, the rear left does not receive a carbon-copy of the surround right channel. There's more to it than that. Sharp directional cues that lean to one side of the room are preserved, and remain directional throughout. Cues that exist on both sides simultaneously are processed proportionally to the rear channels. Any left/right balance is preserved in the algorithm and not shifted in the surround field. In a room with lots of space behind you, it can really fill in a hole. So each rear surround is actually a blend of the surround right and surround left signals. With a 6.1 signal, the results are even better as "guesswork" is replaced with the correct cues.

It was alluded to briefly here, but I think the key factor in 7.1 is room size.

In a small room, you won't benefit much, and could even hinder the sound-field having the 6th and 7th speakers connected. In a room that provides for several feet of space behind the listening position, I find the results are quite significant, and make the extra speakers worthwhile.

The downside to 7.1 is too little space behind you (or improper speaker calibration) and the sound-field collapses to the rear of the room. I don't know exactly what the distance is ideally, but I 4 ft or so is the shortest distance I've heard it sound okay with. I have a friend who has them about 3 ft back and we just can't get the levels right to a point where it doesn't collapse the surround environment.

During my last speaker upgrade I sold off my Paradigm Studio 20's one pair at a time and lived with 5.1 for a few months. When I finally went back to 7.1 I was amazed at how big a difference it can really make. My room just sounds "larger". Hard to describe, but my wife describes it as though 5.1 was like sitting at the rear of the theater and 7.1 somewhere in the middle.

I have the option to apply processing to the 5.1 track and make it a matrixed 7.1 sound-field with any 5.1 source. I'm always comparing the two, on every DVD play (I have to hit a button to manually engage it anyway). I have never found 1 example where it's sounded worse doing so. Sometimes it doesn't improve the sound much at all though depending on the sound track.

Since speakers aren't cheap, I think most people are better served building the best 5.1 system first. That is, don't cheap out on the quality of speakers in order to afford 4 surrounds. Go for quality not quantity if you have to. I think 2 quality surrounds is a better option (especially for multi-channel music if you're into it). But if you get good mileage out of your home theater, have several feet behind you, and have some extra cash, I think adding 2 speakers makes the experience noticeably better.

hydroman
05-10-2007, 11:53 AM
Ok! I admit it!

I thought i knew what 7.1 was. i was wrong. I thought it meant front surround speakers and mains.

So if i understand correctly my set up should be:

Front L&R the big/main Aegis speakers
Center

wall mount surrounds

and move the second set of surrounds to behind me?

Thanks!

GMichael
05-10-2007, 01:54 PM
Ok! I admit it!

I thought i knew what 7.1 was. i was wrong. I thought it meant front surround speakers and mains.

So if i understand correctly my set up should be:

Front L&R the big/main Aegis speakers
Center

wall mount surrounds

and move the second set of surrounds to behind me?

Thanks!

There are some systems that will give you an extra pair of front (presence) speakers. But when most people are talking about 7.1 they are referring to the extra pair in the rear, plus the normal 5.1.

PeruvianSkies
05-10-2007, 02:37 PM
Anytime we have a discussion regarding multiple speakers and surround sound I must laugh and think about the 360-degree sound experience that Michael Jackson was experimenting with back in the 80's by recording a Cow (mooing) with microphones placed in a sphere-like pattern completely around the cow. Then, for playback if you had speakers replacing where the microphones were, the idea was that the listeners could have "perfect placement" of the reproduced sound of the cow. Didn't work out in the end. He sucked. Or should we say ....well, Michael Jackson and Cows....that's just gross.

R.S.
05-15-2007, 10:27 AM
Ok! I admit it!

I thought i knew what 7.1 was. i was wrong. I thought it meant front surround speakers and mains.

So if i understand correctly my set up should be:

Front L&R the big/main Aegis speakers
Center

wall mount surrounds

and move the second set of surrounds to behind me?

Thanks!

I have a similar Harmon Kardon receiver. That receiver will also convert 2 channel stereo to 7.1. I use the 7.1 a lot for headphone type music (psychedelic rock, big orchestra's, etc.) Where there's a lot of instruments, swirling sound effects, and dynamics. It usually does sound quite better. For jazz and small orchestra's, etc. I stick with 2 channel.

The receiver will also convert just about all DVDs to 7.1 (except mono soundtracks I believe.

I do listen to 5.1 when playing many of my highly acclaimed SACDs, which were recorded for 5.1. I want to listen to it the way the musicians/producers wanted it to sound.

StoneMountain
05-28-2007, 06:22 PM
Ok! I admit it!

I thought i knew what 7.1 was. i was wrong. I thought it meant front surround speakers and mains.

So if i understand correctly my set up should be:

Front L&R the big/main Aegis speakers
Center

wall mount surrounds

and move the second set of surrounds to behind me?

Thanks!

Go to the Dolby website. There is a link for room and speaker setup.

http://www.dolby.com/