AVS Forum banner

1 - 20 of 63 Posts

·
Registered
Joined
·
2,403 Posts
Discussion Starter #1
**Updated, added rear center to the mix 2/02/2009, see post #39



*Minor change 1/10/2009

See Post #36



**Updated**

See post #34

22.2 Surround Sound, experimenting in enhancing/expanding 5.1-7.1 formats

Current configuration;





How it got there;


This thread chronicles the progression of the tests to the current configuration.


Some people build model planes and some like to collect coins as a hobby I like to experiment with various aspects of home theatre including seeking surround sound nirvana.


In a previous thread found here I talked about overhead sound I was getting using a CS3X Jr in my experimental HTPC home theatre system I have in a back bedroom. In that thread CAVX clued me on using two CS3X Jr's to get 4 extra channels, left & right overhead and left & right front side axis channels. I tried it and I like it, here is basically what I did;


I ran the left front & left side surround outs to the left front & right front inputs on one CS3X Jr then used its the SP1 output as left side axis and SP2 output as left overhead. Then did the same with right front & right side surround on the other CS3X for the right side axis and right overhead channels.


This creates a surround sound system very similar to Tom Holman's 10.2 surround sound the only real difference was I was using 2 rear surrounds and a single sub.


Here is a good description of Tom's

Introducing the 10.2 Surround Format


The addition of the front side axis channels had a big affect on the sound, it was bigger wider sound and the sound transition from fronts to side surrounds was smooth, it was with out a doubt the biggest impact on the sound of any of the additional channels.


I was so impressed with this I decided to take it a couple steps further and added two more CS3X Jr's to the mix. Using the same technique mentioned above instead using the side and rear surrounds to create rear left & right side axis channels and rear right & left overheads.


In my experimental system I have a HTPC and it has a sound test that sends a helicopter sound to each speaker circling around the all the speakers clockwise and the side axis channels grab it perfectly in between the speakers they are placed between. I have also tested it with the THX Optimizer and between it and the helicopter test they appear to work flawlessly.


Now these new rear channels do not have the same impact as the front side axis channels but they do add to the overall effect. You get smoother front to rear and rear to front sound transitions like drive bys, flyovers, bullet whizzes, explosions etc and fuller more enveloping ambient movie sounds like when background music hits all channels.


It also works great for NFL football games particularly ones being broadcast in DD 5.1 it is like having virtual seat in the stadium with the crowd roars all around.




I did say I took a couple steps; the other thing I did after reading the debates on this big subwoofer thread and coming to the conclusion that to get all the bass possible you really need at least one sub dedicated to LFE and a bass management sub that would get any bass being sent to speakers. So I borrowed one of my M&K 350's from my main theatre and my M&K BMC bass management unit I use for SACD and DVD-A playback in my main theatre.


I set all speakers to large in my experimental system set the 350 as the LFE, and placed it at the front far left of the system. The BMC is only 5.1 so to try get all the bass from all the speakers I ran the sub outs on the four CS3X Jr's to the BMC for the front left & right and surround left & right and used the Center out from the receiver to the Center in on the BMC this way I get most all the bass from all the speakers including the additional channels. I then ran the sub out on the BMC to a small sub and placed it a bout mid way on the right and it works great, I get lows that would not otherwise be produced just using a LFE alone.


CAVX asked for some pictures in that other thread but I never got around to taking or posting any. However this time I did take some mostly to prove I really have this setup.


Now this is a system I use to experiment with, it is a relatively inexpensive system made up of old amps I had lying around, Klipsch THX Promedia speakers ( about as cheap a speaker you can get that still sounds good) and a hodgepodge of speaker stands all in a tight space so it is not pretty. It also does not produce near the quality of sound a high end system in a designated theatre room with adequate spaced out speaker placements, and treatments could but does allow for a good feel of the possibilities.







Note on the overheads; to avoid being beaten about the head by Sanjay or sivadselim it should be stated that it has been established and reiterated time and again there is no designated overhead material in current surround sound formats. What is getting sent up there according to CAVX
Quote:
is a "difference" signal contained in both channels where one channel is out of phase.

I have found what sounds do get up there works provided you calibrate them so that you can't not sit down watch a movie and discern that they are on but can tell when they turned off. If done correctly only the loudest sounds being sent to the overheads should high enough to be audible to your ears yet blend in with the other speakers producing the same sound, like explosions, rocks falling down, plane crashing, echo effects, ambient music etc This should diminish the possibility of distracting out of place sounds and immersion interruption and create deeper immersion, does for me anyway.




In the future I want to use this setup in my main home theatre, when I do I think the best way would be to use the same speakers I am using for the fronts, for the front side axis the rest matching surrounds. Three subs, two for LFE and one for BM sub, I also think using di or tri poles for the overheads for better sound diffusion from above would be better than direct radiating and reduce the chance of any distracting sounds from above being detected. Also I think I may add yet two more CS3X Jr's for left and right center overheads for six overhead channels using the front and rear side axis channels to derive them.
 

·
Banned
Joined
·
5,125 Posts
I like it so how much does the (CS3X Jr’s) go for today, they’ve been out for quite a few years now, so the prices must have dropped. The only other way I would do this is with matching Dolby pro-logic processors and slight bit of hand, some patience and hey presto I have sound images in places along the sidewalls, and I’m not referring to the common based Dolby-EX.


Keep up the good work mate it looks good.



You mentioned (phase) if you use the THX Optimizer mode, where it tests the surrounds with (phasing) and if you have a common Dolby pro-logic decoded connected to the stereo surrounds and use all its outputs.


Left is usual the front, but now it’s used for left sidewall surround.

Centre is usual the front, but now its used centre back surround

Right is usual the front, but now it’s used for right sidewall surround


And last but not least the matrix rear surround that was commonly used for rear surround when it detected a phase change in the mix, it was reproduced behind you!


But due to channel crosstalk music from fronts often speech dialogue was heard, depending on how well the Dolby stereo 4:2:4 mix was done, you’d never really notice any distraction.


So yes with the THX Optimizer mode when it cycles though the phasing and when it goes to out-off-phase its reproduced on the matrix rear, or height channel if that makes things better.


Apollo 13 has some crazy mixing going on the stereo surrounds, when the crew fires the LEM’S engine for short burn, you can hear in the mission control room the sound bouncing around on the surrounds and above me for a brief exciting moment.
 

·
Registered
Joined
·
2,403 Posts
Discussion Starter #3

Quote:
Originally Posted by JBLsound4645 /forum/post/12910754


I like it so how much does the (CS3X Jr's) go for today, they've been out for quite a few years now, so the prices must have dropped. The only other way I would do this is with matching Dolby pro-logic processors and slight bit of hand, some patience and hey presto I have sound images in places along the sidewalls, and I'm not referring to the common based Dolby-EX.


Keep up the good work mate it looks good.

Yes you should be able to do it with matching Dolby pro-logic processors, I thought of that too but the downside is they are big and will give of a lot of heat. Where the CS3X Jr's are small thus easy to hide away out of sight and give off very little heat. Plus the CS3X Jr.s can be had for pretty cheap I got mine from Ebay for $75 each brand new.
 

·
Banned
Joined
·
5,125 Posts

Quote:
Originally Posted by Socio /forum/post/12910899


Yes you should be able to do it with matching Dolby pro-logic processors, I thought of that too but the downside is they are big and will give of a lot of heat. Where the CS3X Jr's are small thus easy to hide away out of sight and give off very little heat. Plus the CS3X Jr.s can be had for pretty cheap I got mine from Ebay for $75 each brand new.

Wow that’s a wicked bargain I would say. There was an article published a few years back in Widescreen magazine, the (CS3X Jr’s) was under the scope for the test of five-screen reproduction in the home, the SDDS8 channel or Todd-AO format and you know what it really worked. I used a few mismatching Dolby pro-logic decoders at the time, because that was all I hand on hand.


I wouldn’t mind if I could get hold of a few more Yamaha DSR-70pro but this model was obsolete around 1992 I guess, it first came out around late 1989 early 1990, not a bad Dolby pro-logic processor.


Mate if I had the bottle to buy off, of the Ebay site I would gladly buy a handful. I don’t think there’s supplier I the UK that supplies (Smart CS3X Jr’s)?
 

·
Registered
Joined
·
34 Posts
Nice work mate,


I also use a 10.2 system comprising of a Yamaha Z9 and an Yamaha A1 for the rears.

Your right it works very well, i actually did it by accident while trying to get the extra centre rear with a Yamaha dspa 1000 running from the rear outputs of the A1 many years ago, then just added the extra high rear speakers although i have put mine far back just behind the rear centre.

Obviously with the Yamaha you get the extra front presence channels which add a soft extra ambient edge to the sound and better localisation to the projector screen.

Also i use 3 subs 1 left 1 right and 1 in the centre between the front mains, using all kef speakers and sub plus mission di-poles and then two paradigms, just for overkill i'm adding some jl diy subs, when they are finished.


It also works very well with music.


Would love the Yamaha Z11 which has it all built in, but will have to wait till the price drops as they do.


The only problem is all the speakers, but its worth it especially with a great action movie !


You must put in your home cinema room when you get chance
 

·
Registered
Joined
·
2,403 Posts
Discussion Starter #6
The Yamaha Z11 has CINEMA DSP HD3 gives you extra front and rear presence channels.


I have the real old Yamaha DSP-1 I used it before there was 5.1 surround sound, in fact I am using the old 4 channel amp I used to use with it to drive the overheads now and it has front and rear presence channels. If the ones in the Z11 are the same as the old DSP-1 then these channels were designed to go high above and behind the front left and right and in the rear at the same height as the front presences.


It was great for music and movies back then but I tried it again a couple years ago did not like it as much with 5.1-7.1 surround sound. I think the CS3X Jr's overhead sound is better for movies as the presence channel puts constant ambient sound where the CS3X Jr's overhead calibrated right only puts sound above you when it is has the most impact.


However one could get the Yamaha Z11 and 6 CS3X Jr's and have 7.1 plus front and rear side axis channels, 6 overhead, and front and rear presence channels for a 21.1 surround sound system.


If I ever come across another 4-5 channel amp and four more speakers for cheap I might break out my old DSP-1 and try adding presence channels in to my experimental systems mix just to see how it sounds however. I think fronts might be ok but not so sure about rear ones.
 

·
Registered
Joined
·
2,403 Posts
Discussion Starter #7

Quote:
Originally Posted by JBLsound4645 /forum/post/12910999


Wow that's a wicked bargain I would say. There was an article published a few years back in Widescreen magazine, the (CS3X Jr's) was under the scope for the test of five-screen reproduction in the home, the SDDS8 channel or Todd-AO format and you know what it really worked. I used a few mismatching Dolby pro-logic decoders at the time, because that was all I hand on hand.


I wouldn't mind if I could get hold of a few more Yamaha DSR-70pro but this model was obsolete around 1992 I guess, it first came out around late 1989 early 1990, not a bad Dolby pro-logic processor.


Mate if I had the bottle to buy off, of the Ebay site I would gladly buy a handful. I don't think there's supplier I the UK that supplies (Smart CS3X Jr's)?

Yea it is a good deal considering they used to be over $300 US if memory serves. As to where to get them in the UK I have no idea, try googling to see if anyone ships there.
 

·
Banned
Joined
·
5,125 Posts
Yeah that’s right I was looking around last night, while you was talking to the other member. I was trying to find the article link on finding more channels or something like that, I just can’t remember the title, I tried a dozen or so keyword names and only few other articles, not quite relating to the (Smart CS3X Jr’s) but interesting reading.


This link is still active on the secrets site, Dolby-EX with Smart, but the one was trying to hunt down was, finding more channels SDDS8?
http://www.hometheaterhifi.com/volum...arch-2000.html


Still if you don’t mind reading though these articles that are published in Mix, I occasionally used buy this magazine a each month from Borders, still have a few around.

Pearl Harbor
http://mixonline.com/mag/audio_pearl_harbor/

The Patriot
http://mixguides.com/consoles/tips_a...ot-movie-0700/
 

·
Registered
Joined
·
3,258 Posts
What about the front height channels? This seems to me to be a fundamental advance which both Tom Holman and David Griesinger have in their proposed 10.2 systems. Yes, one can try to synthesize height channels, as one receiver manufacturer has done for years. But it is not the same thing as having such channels separately mixed and recorded. IMAX has just a single height channel, and I think it adds an amazing amount of spatial accuracy to the front sound.


Regards,

Terry
 

·
Banned
Joined
·
5,125 Posts
There’s a nice line in Apollo 13 “Jim you’re all set” this line is heard on (left and right) front only, while the centre channel carries Foley effects and music, same with left right with the music.




I can place that information ether above the centre channel, or I can mix it, into the centre channel across the normal matching LCR fronts, so there are many possibilities to this, all of them feasible.


There’s also a similar effect in Die Hard with a Vengeance, where Simon, phones up a radio station, his voice is only heard on left and right while the DJ is placed in the centre channel.


I can do many things with my home cinema to create an atmosphere, that is slightly different from the one down the road.
 

·
Registered
Joined
·
2,403 Posts
Discussion Starter #11

Quote:
Originally Posted by Terry Montlick /forum/post/12915951


What about the front height channels? This seems to me to be a fundamental advance which both Tom Holman and David Griesinger have in their proposed 10.2 systems. Yes, one can try to synthesize height channels, as one receiver manufacturer has done for years. But it is not the same thing as having such channels separately mixed and recorded. IMAX has just a single height channel, and I think it adds an amazing amount of spatial accuracy to the front sound.


Regards,

Terry

Are not both the Tom Holman 10.2 and the David Griesinger's overhead or height channels just matrix derived same as the ones in my test system?


I agree having height mixed versus synthesizing them would be much better but for now if you want them synthesizing is the only way for now. However it is my understanding that DTS MA does support an overhead channel so maybe we will get real overhead mixes in the future.


By the way who makes the receiver that has the ability to synthesize height channels? I know a couple that can do front side axis but never heard of one that does height.
 

·
Registered
Joined
·
34 Posts
Hi i think Yamaha are the only ones to provide front height presence channels, all their top of the line av amps have them and next from top usually have them.


They work very well, there is some form of processing going on not sure what, but they are certainly missed when not on.


I dont think any one else has bothered to pay Yamaha as they have the patent on them, one other top of the line processors has 4 assignable channels which maybe could be used not 100% sure but think it could be the lexicon mc12.


By the way how many speakers are you using ?
 

·
Registered
Joined
·
3,258 Posts
Yes, I was thinking of the Yamaha presence speakers, which are placed up high.


- Terry
 

·
Registered
Joined
·
29,963 Posts

Quote:
Originally Posted by Socio /forum/post/12921517


Are not both the Tom Holman 10.2 and the David Griesinger's overhead or height channels just matrix derived same as the ones in my test system?

No, both use discretely recorded height info.
Quote:
By the way who makes the receiver that has the ability to synthesize height channels? I know a couple that can do front side axis but never heard of one that does height.

No receivers synthesize height channels. Yamaha receivers generate reverb and early reflections, sending the added information to 'presense' speakers placed higher and wider than the front L/R speakers. This expands the front soundstage and simulates the effect of being in a larger listening space.


The main difference between what you're doing and what the Yamaha DSP modes are doing is that they are adding information to the recording while you're extracting information from the recording. Ambience extraction uses more speakers to stabilize imaging in the soundstage, while ambience generation using more speakers is better suited for room simulation.


Sanjay
 

·
Registered
Joined
·
2,403 Posts
Discussion Starter #15

Quote:
Originally Posted by Import racer /forum/post/12922034


Hi i think Yamaha are the only ones to provide front height presence channels, all their top of the line av amps have them and next from top usually have them.


They work very well, there is some form of processing going on not sure what, but they are certainly missed when not on.


I dont think any one else has bothered to pay Yamaha as they have the patent on them, one other top of the line processors has 4 assignable channels which maybe could be used not 100% sure but think it could be the lexicon mc12.


By the way how many speakers are you using ?

I mentioned the Yamaha one a few posts up did not think that was what Terry Montlick was referring to. Those are more for ambiance and would indeed make the front stage bigger/taller and more spacial but they are not the same as the ones being derived using the CS3X Jr. However the addition of two front presence channels lifting the sound higher could create an even better sound blend between the front stage and the CS3X Jr derived overheads.


The Parasound Halo is the one that has the extra 4 customizable channels.


On how many speakers; I am using the 7 speakers from my original 7.1 setup plus 4 for side axis speakers and 4 overhead so 15 total plus 2 subs.
 

·
Registered
Joined
·
2,403 Posts
Discussion Starter #16

Quote:
Originally Posted by sdurani /forum/post/12922375


Yamaha receivers generate reverb and early reflections, sending the added information to 'presense' speakers placed higher and wider than the front L/R speakers. This expands the front soundstage and simulates the effect of being in a larger listening space.


The main difference between what you're doing and what the Yamaha DSP modes are doing is that they are adding information to the recording while you're extracting information from the recording. Ambience extraction uses more speakers to stabilize imaging in the soundstage, while ambience generation using more speakers is better suited for room simulation.


Sanjay

Interesting, I always thought the sound from presence channels were just extracted and manipulated existing sound then reproduced in its altered form not adding additional info to create them.


Perhaps a marriage of both extraction created sound and the generated presence sound might be the best way to go. I am going to have to try it when I can and see.
 

·
Registered
Joined
·
3,258 Posts
I think around 3 more years for the old Yamaha patent to expire in the US. Then this invention becomes public domain.
 

·
Registered
Joined
·
34 Posts
Nice theater and info,


Never thought of building in the speakers like that it looks great !


I have 17 speakers in total so far plus two extra subs going in when the boxes have been finished being sprayed, which includes 3 centres and two smaller speakers on top of the normal rears to diffuse the sound a little, plus the normal set.

Also two more kef floorstanders off e-bay on there way so hiding them all would be great as so many is getting a little oppressive to look at.


How are the extra 2 fronts controlled ? are they delayed with a Cs3x ?
 

·
Banned
Joined
·
5,125 Posts
I think home or cinema should go to the extreme, but I’ve heard that there’s a good sound system at Disney, I might be wrong.


What about 9 channel screen sound with sounds that can be moved in three directions from the left. Below middle and above, same goes with centre and right channel.


The same again with the surrounds below middle and above, I think the application for something like this would create a nightmare for sound mixers; I mean they’ll be working literally around clock to create the best mix presented by all these channels. LOL 17.1 now that’s insane, but doable.
 

·
Registered
Joined
·
3,258 Posts

Quote:
Originally Posted by JBLsound4645 /forum/post/12926736


...I’ve heard that there’s a good sound system at Disney, I might be wrong.

Disney utilized the first commercial multichannel sound format -- in 1940!
This was called "Fantasound," and was developed along with RCA. The movie that used it was, of course, "Fantasia." There were 4 soundtracks recorded on film. Three were for program material mostly coming out of left, center, and right front speakers, and the fourth was a control track. The control track provided gain information to increase dynamic range by 50 dB. The 4 soundtracks were on a separate 35mm film running in sync. There were also rear left and right speakers, which got switched in to receive rerouted front left and right program channels at particular spots in the film. This switching was done manually for the 8 roadshows, and eventually automatically via relays (switched from notches on the film edge) in one LA theater.


5 channel sound. Not bad for nearly 7 decades ago.



Regards,

Terry
 
  • Like
Reactions: VonDrake
1 - 20 of 63 Posts
Top