Surround Backs, together or...

jakelm

apart?

I have read many different ways of placing the surround backs, in a 7.1 system.

I dont want to bring the name up again (I know how popular it is around here,,,LOL), but THX has surround backs together and I have read in other forums and A/V sites, having the surround backs split apart.

My back wall is about 8' behind the listening postion and 16' wide.

What are some of your opinions?

Jake

jakelm

Here in crutchfeild, you see the surround backs are split.

http://www.crutchfieldadvisor.com/learningcenter/home/speaker_placement.html

Here in THX you see they are together.

http://thx.com/home/setup/speakers/71.html

engtaz

HK manual should show you the proper way.


FL_________C_______FR




SL______SEATS_____SR

______RL______RR_____

Gaara

Jake,

I had the same question a while back and did lots of research and lots of testing. I ended up going with the 1.2 method, that is take the distance from your head to the back wall x 1.2 = distance to have rear speakers apart.

I am 5ft in front of the back wall and have my speakers 6ft apart. I much prefer this to the THX method which I originally did, which had my speakers 2ft apart. With the speakers so close together it sounded like one rear surround, while with them 6ft apart I distinctly hear two speakers. Sound effects that pan around the rear sound field also sound much more spacious and realistic.

Jared

jakelm

engtaz wrote: »

HK manual should show you the proper way.


FL_________C_______FR




SL______SEATS_____SR

______RL______RR_____

I have it the same way. But I did want to hear opinions.

The THX site brought up a few questions about placement. They do specialize in surround sound.

jakelm

Gaara wrote: »

Jake,

I had the same question a while back and did lots of research and lots of testing. I ended up going with the 1.2 method, that is take the distance from your head to the back wall x 1.2 = distance to have rear speakers apart.

I am 5ft in front of the back wall and have my speakers 6ft apart. I much prefer this to the THX method which I originally did, which had my speakers 2ft apart. With the speakers so close together it sounded like one rear surround, while with them 6ft apart I distinctly hear two speakers. Sound effects that pan around the rear sound field also sound much more spacious and realistic.

Jared

Jared, while I understand and practice this method. The surround backs are not stereo speakers, rather mono/matrix. So seperation is in question.

schwarcw

jakelm wrote: »

Jared, while I understand and practice this method. The surround backs are not stereo speakers, rather mono/matrix. So seperation is in question.

They should be stereo, otherwise why would you need a rear center?

jakelm

schwarcw wrote: »

They should be stereo, otherwise why would you need a rear center?

Im not following you here. Are you saying the SBL and SBR are in stereo?
I thought they were a matrixed 6th channel.

Systems

jakelm wrote: »

I thought they were a matrixed 6th channel.

I believe this is correct atleast for Dolby Digital EX as the backs are mono derivived from the SL and SR.

Some claim that when using a single rear or placing the 2 backs close togehter in the middle can have the effect of the sound apearing to originate from the front instead of the rear.Separating them eliminates this.

engtaz

you calibrate all speakers with a sound meter ( Rat Shak) from your listening area. This helps even out the distance you are away from your speakers. You will be surprised at how you adjustments come out.

wingnut4772

I believe dolby PLIIx is stereo.

jakelm

wingnut4772 wrote: »

I believe dolby PLIIx is stereo.

Thats the first time I hear that for surround backs.

jakelm

engtaz wrote: »

you calibrate all speakers with a sound meter ( Rat Shak) from your listening area. This helps even out the distance you are away from your speakers. You will be surprised at how you adjustments come out.

Been there, done that. My HK does an excellent job of that with the Ez/Eq.

wingnut4772

jakelm wrote: »

Thats the first time I hear that for surround backs.

Here's the second time:p

First, PLIIx extracts two additional, true-stereo "back surround" channels from the original 2+-channel source, using enhanced steering logic to interpret spatial cues (derived either from amplitude and phase relationships in stereo material, or from matrixed information encoded specifically for compatibility with the PLIIx processing). As with PLII, all front, surround and back channel information is delivered in full-bandwith (20Hz - 20kHz) audio, resulting in a fully enveloping, immersive surround experience with precise directionality and an enlarged optimum listening area (or "sweet spot").

jakelm

Not to change the subject, but there is one thing that baffles me.

Star wars is 5.1EX. I select that setting in the SW menu, but my HK only plays in 5.1. I thought the "EX" is a 6th channel? When I force 7.1DD with my HK, the 2 surround backs are playing but the diplay on the AVR shows that they are forced from the reciever and not part of the soundtrack.

jakelm

wingnut4772 wrote: »

Here's the second time:p

I learn something everyday. I had no idea that they were "true stereo". How can PLIIx have tru sereo surround back (not surround side) when the "x" represents only one channel (6.1 not 7.1)?

Systems

http://www.dolby.com/consumer/technology/prologic_IIx.html

engtaz

good link great info.
Thanks

Systems

engtaz wrote: »

good link great info.
Thanks

Yeh, that Dolby site is very informative
Your welcome,

jakelm

thanks GV.