[Housteau]

I posted a similar question on another forum, but with the in depth discussions I have read here and the wealth of knowledgeable folks that participate, I thought this may be the better venue.  To begin with, I am not that familiar with multichannel surround applications intended for ‘high end' music reproduction.  Although I am familiar with the typical home theater systems for video.  I do see these set-ups as having different goals and so not always 100% fully compatible with each other.  Is there a website or group that is dedicated more towards the music and away from the theater side of things?  I would be interested in learning more about the possibilities.

I have also noticed a lot of different formats out there being mentioned.  I have seen 4.0, 5.0, 5.1, 6.0 and 7.1.  

I assume 4.0 uses two full range front speakers without sub or center.  This makes sense to me, because it preserves the created center image from that stereo pair.  I would think a system like that would be ideal in mixed listening of stereo and multichannel recordings as the front speakers are in the ideal location for both.  Actually a 4.2 system (dual subs) would be the ticket.  However, the pure 4.0 systems and info about them are rare and have been reserved mostly for critical use in mastering and demonstrations, from what I have been lead to believe.

I also assume that 5.0 uses 2 full range fronts with a center.  5.1 we all know. 7.1 must be a 5.1 with the addition of two side speakers, but what is 6.0?  Would that be an addition of a rear center speaker?

The part that confuses me about all of this, is why add a center speaker if you have already created that space with your original stereo pair and lets assume that it has been done correctly?  For video dialogue it is important, but for music?  I can see that it would widen the sweet spot for listening, but is something not taken away by introducing that center channel, something that was made special by your careful placement and set-up of your original pair?  I'm asking because I really do not know.  With the addition of that center channel, do your front speakers now need to be repositioned and to a spot not then ideal for stereo reproduction?  In which case, can a 5.1 (7.1 etc.) system be set-up to get the absolute best from both worlds without compromise?

I understand that there is not really a standard for recording out there either.  Some disks are being mastered with different ideas (effects) in mind.  Some try to show off all the channels by providing something there that may not have been in a natural acoustic space at the time.  Once again, special effects and surrounding the listener with sounds is fine for video and in fact expected, but it can and often lowers the standard for high end music.  From what I have been told, Dark Side of the Moon was done correctly.  That is a ray of hope, but will that trend continue into the mass market releases, or will they cater to the special effect video-like recordings of the general DVD and CD buying public?

Is it possible that the video revolution being largely responsible for the rebirth of surround sound, will continue to be the driving force in how it will be presented to the consumer?  I don't think that it is only possible, but a certainty.  I hope that I am wrong and also for those of us that are critical listeners will not have to continue to play catch-up as we did when the "perfect sound forever" CD was released.

Dave

[Sedona Sky Sound]

Hello Housteau,
You can also add 3.1 to that list of numbers  . I posted a Trinaural Processor review on my website that might answer a few of your question on how a Center Channel can be implemented:

http://www.sedonaskysound.com/trinaural%20processor%20reviewi.htm

While I am not overly thrilled with some of the implementations of multi-channel SACD/DVD-A, there are a few theoretical benefits. The first is that music is spread out over more drivers. All things being equal (and they never are), more driver/cone area can mean a "fuller" sound.

Also, more speakers means less "congestion" of the music. If you have a sax, upright bass, and vocals all coming out of one speaker, then there can be some amount of "congestion" as the mid driver tries to play all three sounds at once (which most quality drivers can do quite well but not perfectly). However, if you spread those three things over three different speakers, then each speaker can produce an uncompromised signal.    

Multi-channel music can also help mask the inherent limitations of some speakers. For example, multi-channel music can help create a false soundstage for speakers not capable of reproducing a good soundstage in 2-channel.  

I am sure there are lots of other theoretically good reasons, but I can't think of them right now   .

As for room set-up for multi-channel Audio versus Home Theater, there can be a few differences. Since most SACD implementations do not provide for digital delay, you ideally want all speakers equidistant from the primary listening position. This is not nearly as important in HT since most HT Processors allow you to program in a digital delay so that you rear speakers can be placed closer or farther from your listening position.

Most people who like to watch movies also want their rear channels to be dipoles to get a more diffuse/non-directional sound. For Audio, all the standards are based upon direct radiating monopole speakers. The 7.1 HT standards also use non-directional speakers for the sides which would be contrary to what an Audiophiles would want.      

Hope this helps get the discussion going. Happy listening.

Julian
www.sedonaskysound.com

[Housteau]

Julian,

Thank you.  Your post and the link to your review is a very good start indeed.  3.1, consider it added .

In your review you stated:  

"However, by careful configuration you can use the bypass inputs to allow for regular Stereo for when your friends come by."

Could you explain that in a little more detail, because that would answer one of my primary questions about the other multichannel systems.  Can both stereo and multichannel exist together without compromise?  Will the Trinaural speaker placement work for stereo?  It looks to be a wide spread on the diagram, but possibly ideal for nearfield listening.

Dave

[John Casler]

Hi Dave,

Yes, the Audio/HT world is no longer as simple as it once was.  Julian offers some excellent information and guidance, and with the introduction of the TriNaural Processor it poses even more options and questions.

First you have:

2 Channel Music
3 Channel TriNaural Music

Then you have:

5.1 HT
5.1 Multichannel Music
6.1 HT
7.1 HT

Of course you also have everything in between, but those are the break points, not to mention various processing systems within some of them. (THX/THXex/DTS/DD/Logic7/DTSneo/DVDA/SACD/etc/etc)

Regarding speaker set up:

2 channel Music we all know
3 channel music can be viewed at the URL Julian posted or on the Spread Spectrum Website as below

When we get to 5.1 HT vs 5.1 Multichannel Music we get into sticky territory.

The requirement for 5.1 music while demanding, is not "as" demanding as that of multi-channel music.  Even with the advent of Dolby Digital and 5 seperate channels being processed, most of the time it is ambient, or directional cueing sounds and they are only foley, or "manufactured" sounds and not even real.

Multi-channel music however is a different story (or at least it is supposed to be) where we "are" attempting to do the same thing we do with the front channels and that is to "match" the tone and timbre.

To really do this "wall mounting" must go out the window since even if we use the exact same speaker for all 5 channels, if some speakers are mounted on the wall, above our heads, and some are off the wall, and on axis, the tone and sonic character will not match.

The modified ITU set up is probably the simplest and best.

As far as what speakers to use, I like to do something like the following:

Frontal array= RM40 Mains with LRC center (only somewhat compromised for Multi-channel music or TriNaural)

Side Surrounds = RM1 with selectable Dipole stacked on top both sitting the same distance from the wall and listener as the mains. (this effectively creates a selectable "TriPole" which can be activated as needed depending on sofware)

Rear Surrounds = the same as the sides, with a monopole and dipole selectable.

But reality creeps in and compromises are made.  Unless you have a dedicated room you may not be able to use these suggestions.  Some even have a dedicated room and cannot/willnot entertain the idea of "non-wall hanging" surrounds (go figure )

In any event, that is my ideal, and it just depends on how many compromises must be made as to the end result, for the particular processing mode, or software selected.

[Sedona Sky Sound]

Hello Dave,
You asked a very good question, but I am not sure if I have a good answer. I think it depends on your definition of compromise, the size/layout of your room of your room, and what you are willing to do when you want to switch between the two. To keep things as simple as possible, lets leave the Trianaural out of the picture for a second.

From a sonic perspective, it is possible to have a sytem that plays both milti-channel SACDs and regular SACDs very well. What will this require? A pretty large room (30+ feet in length perhaps) and several 2-channel pre-amps. The large room is required since you want to be equidistant from all the speakers but do not want to be in the center of the room (bass null). Personally, I have not heard a single multi-channel pre-amp or pre-amp processor (pre/pro) that I viewed as being equal to a good stereo pre-amp (there may be one, but I personally have not heard it). Even in analog bypass mode, all the pre/pros I have heard (Theta, Aragon, etc.) were far worse than a decent Stereo pre-amp. The compromise here is that you now have to manually change the volume on three different pre-amps (and the matching that requires).

If you want to play movies, and thus require a pre-amp processor, then you may have to compromise a little on the SACD/DVD-A quality. This is the compromise I ended up with in my demo system. I have a two-channel pre-amp that I use for Stereo and a pre/pro with analog bypass for my movies and SACD/DVD-A. In my case, I just switch the interconnect going to my amp when I want to switch between them (takes maybe two minutes).

However, with the Trinaural in the system, all I had to do is flip a switch on the front of the Trinaural. The Trinaural always stays hooked to the L/R and center speakers (and sub if you want). Both my Stereo pre-amp and the multi-channel processor were plugged into the Trinaural. Here is what can be done to listen to the different modes:

Trinaural: Stereo pre-amp is "on", pre/pro is "off", Trinaural is "on"
SACD/DVD-A: Stereo pre-amp is "off", pre/pro is "on" in analog bypass mode, Trinaural is "off"
Stereo: Stereo pre-amp is "off", pre/pro is "on" in analog bypass mode, Trinaural is "off" (my pre/pro performance in Stereo is unfortunately a compromise I cannot live with)
Movies: Stereo pre-amp is "off", pre/pro is "on" in Digital mode, Trinaural is "off"

Depending on whether you listen in Nearfield or not, and what speakers you use,  the Trinaural placement may or may not work perfectly for you. The placement that James recommends for the Trinaural is virtually the same as what Brian recommends for VMPS speakers (at least as far as toe-in is concerned). With minimal toe-in speakers, the difference will likely be a little greater. To get everything equidistant when using the Trinaural, I had to move the L/R speakers out a little from where I though "optimal" Stereo positioning was associated with my room. If my room was slightly wider, I think the "triangle" would have been just about correct for both set-ups.

Julian
www.sedonaskysound.com

[Housteau]

Thanks guys.  That is a lot of good info.

John, that is a good description and explanation of the differences between the theories of multichannel Music and HT sound and requirements.  So, as of now, 3.1 and 5.1 are the music standards, and the rest (7.1 etc.) are meant for HT?  That does simplify things a bit.

Julian, I can see how multichannel would require a good sized room to work with.  You are a fan of short cable runs, so I guess this is one of those compromises as well.  The room acoustics would also be set-up differently for multichannel, wouldn't they? (maybe not so much for Trinaural) Well, I guess that would depend if one liked more of a diffusive environment for stereo or not, as I do.  I think of multichannel (5.1 etc.) as requiring a room that is more damped as not to smear the dedicated signals coming from the multiple speakers.  If this is so, then switching back to stereo from multi would add in one other obstacle to deal with and not give a true A - B comparison.

By some of these room requirement descriptions, the use of the long wall may possibly make for an ideal Trinaural  set-up.  A very interesting discussion indeed.

Are any of you familiar with the Audio Research surround processor?  I have only heard it once.  My impression was that of a higher quality Haffler rear channel extraction unit.  It separates out the rear channel material naturally found within two channel recordings.  I wonder how that would work added to a Trinaural set-up?

Dave

[meilankev]

Dave,

My "main" Home Theater is a 4.0 system, and is anchored by RM40s up front driven by tubed monoblocks.  There is no center speaker to "muddy things up".  As my listening room is small, the subwoofers I have tried gave little benefit - so I do without.

I have been "enlightened" to the potential benefits of multi-channel audio formats (how the surrounds/rears can be skillfully used to provide proper ambience and spatial clues to more accurately recreate specific musical venues).  Despite this capability, I still much prefer listening to this hi-resolution format (DVD-Audio) in 2-channel.  I admit, it's an apples and oranges comparison in my case, as my HT amp and surround speakers are considerably lower quality than my 2-channel gear.

My hypothetical opinion on the need of Center Speaker is as follows:
> A Center Speaker is much more important on Home Theaters that have a physical "presence" between the Main Speakers.  By "presence", I mean Entertainment Center, Rear Projection TV, etc.  Seeing as how these devices detract from stereo imaging for 2-channel music, it only follows that they would break down dialog/et al during DVDs.  Hence the need for a Center Speaker.
> A Center Speaker is less important for Home Theaters that use either a Front Projector (like mine) or a TV that could possibly be hung on the front wall (like a plasma).  If there's nothing to bother the stereo image for 2-channel music, then this should also allow for better center imaging for movies.

Good luck,
Kevin

[Housteau]

Kevin,  that sounds like good solid reasoning why a center channel would be necessary.

Julian - John, I am surprised to hear that most multichannel preamps appear compromised.  Are there any designed and dedicated strictly for multichannel music minus the HT decoders?

I also wanted to ask about the toe-in recomendation for VMPS speakers.  I was curious as to what you fellows hear when these speakers are crossed 1' in front of you, compared to direct beaming and then crossing just behind your head.  How does the image appear to change to you?

Dave

[John Casler]

Julian - John, I am surprised to hear that most multichannel preamps appear compromised.  Are there any designed and dedicated strictly for multichannel music minus the HT decoders?

Dave

Hi Dave,

I don't know if I would say the Pre/Pros are compomised as much as the fact that speakers and the way we set them up is a group of compromises.  These compromises are usually dictated by aesthetics, room limitations, Significant Others, and the fact that some processing modes or softwares require differing set ups to be used most effectively.

At this time all multi-channel music processing is not a function of the Pre/Pro, but the DVD player and software.  The two main processes being SACD and DVDA.  All processing of these software is done in the DVD player and not the Pre/Pro, which is different than what goes on in 5.1 Movies. (although player processing is available on some)

These Multi-Channel Music players have 5.1 analog outputs that then are input through "analog" inputs on the Pre/Pros.  So, except for some Pre/Pro units offering some "bass management", the Pre/Pros are just gain control devices.

I also wanted to ask about the toe-in recomendation for VMPS speakers.  I was curious as to what you fellows hear when these speakers are crossed 1' in front of you, compared to direct beaming and then crossing just behind your head.  How does the image appear to change to you?

I prefer the "on axis" response and have my system adjusted for that position.  I would liken it to headphone accuracy, with directional cues, perfect soundstage and limited room interation when combined with nearfield listening positions.

I find that slightly off axis, softens the detail and highs slightly, due to the reduced dispersion.  This effect is less with the FST than with the Spiral Ribbons.

For those desiring a slightly larger Sweet spot, having the speakers toed in to converge 1-2' in front of you will slightly increase the "width" of the sweet spot, especially with the FST.

It seems that for some reason, many prefer to set up their rooms the "long" way, which introduces any number of problems associated with the room, of which early side and ceiling reflections are the main ones.

By converging well in front of you, the side reflections (especially in a low dispersion speaker) are reduced and this will improve the soundstage.

Converging behind you can also offer some increased perception of actually being "in" the perfromance.

This might be my second favorite, since I like a wide soundstage and this produces that.  I don't find that any part of the image suffers (I have had my 626Rs over 12 feet apart while listening no more than 7 feet from the front line (in the center) of the speakers with incredible results.

I recently had a client visit from Philly who brought along his sister (a budding audiophile) and she "seriously" prefered the speakers convering behind her head and sat well forward on the listening sofa for most of the session.  She said she loved feeling like she was really "in" the performance.

If one listens with a frontal or rear convergence on a regular basis, it might mean that the pots may have to be adjusted slightly up in order to acheive the same kind of delicacy of detail that is acheived with an "on axis" position.

Hope that helps

[Sedona Sky Sound]

Hello Dave,
There are several analog only 6-channel pre-amps that have hit the market in the last year or so:

The Bel Canto Pre6: http://www.belcantodesign.com/index2.html
Vaza: http://www.adireaudio.com/home_audio/electronics/vaza.htm
EmmLabs Switchman: http://www.emmlabs.com/
Accuphase: http://www.accuphase.com/cx-260_e.htm
plus several more....

At CES and T.H.E. Show last year,  I think I heard 2 different "production" multi-channel preamps and another 2 or 3 prototypes (I was actively looking for a pre-amp line to carry so this was my primary focus). Unfortunately, I can't find my notes and do not remember which ones I heard (after 3 days of listening to probably 75+ systems, things tend to run together a little   ). I do remember that none of them made me go "wow" and there was one or two that I would actively put in the "bad" category. Of course, listening at CES is no substitute for listening in your own setup with your own gear (but it does help establish trends and the "good" products seem to really stand out from the rest).  

My comment on the analog pass-throughs of pre/pros sounding worse than stand-alone pre-amps is based upon first-hand testing in my demo room as well as those of my friends. I think the main reasons for this are:

1) The EMI/RFI of all the additional "stuff" in the case effects the analog signal path
2) Marketing/competition/pricing pressure requires the manufactureres to save money by putting in lower quality components in Pre/Pros
3) Tendency to mix digital and analog circuitry (i.e., digital volume control) instead of having a true "all analog" circuit
4) Design cannot be as efficient as possible since the designer must also deal with digital issues

As for on/off axis listening, I think the room has a lot to do with that. In my 14 foot wide, slightly dead room, I was unable to obtain perfect  imaging with the speakers crossing behind me. Directly on-axis, the imaging was there but the tweeters were hot and I felt like I was missing some soundstage. If I remember correctly, John has cranked his tweeter pot down quite a bit (10 o'clock?) which sounds correct given the on-axis listening.  

Crossing directly in front of the listening position provided pinpoint imaging and a wide soundstage for my room. At CES, Brian told me that the best frequency response of the new FST were actually a few degrees off-axis. In my system, the tweeter pot is set at about 1' oclock position and the mid pot is at about 12:30.      

Julian
www.sedonaskysound.com

[cinema&sound]

I would point out that this dicussion is VERY skewed to music repoduction at the expense of movie track repoduction.

John is correct that the ITU speaker is what SACD and DVD audio expect.
DVD movies (Dolby Digital, DTS, DPL-II, and THX etc.) do NOT.

The room itself determines whether 5.1 7.1 can be optomized and if they make sense.

Remember that 7.1's goal is to make the sound track of movies most enjoyable to a wider group of people (more / multi-row) in the listening environment. It is not primarily to increase the enjoyment of the "sweet spot". It also opens the palette of sound effects and panning effects for both muti-channel movies and music. It does not however decrease the sweet spot, it is the other things, like John discusses with speaker placement that effect those sensations.

7.1 makes a lot of sense to someone who whats to enjoy the experience. It is not yet a audiophile standard, but to the audiophile, it is the journey not the destination that is the true value of the hobby (experience). (like most hobbies)

[Housteau]

"I would point out that this dicussion is VERY skewed to music repoduction at the expense of movie track repoduction."

Yes.  That was my intent on starting this thread.  Surround sound for music does not have as high a profile as it does for HT.  I wanted to explore the differences in rooms, equipment, set-up and theory strictly for music.  Also, high on my list was to see how compatable it could be with the more purist traditional 2 channel listening that I am used to, and would not want to bargin down.

Dave

[John Casler]

I would point out that this dicussion is VERY skewed to music repoduction at the expense of movie track repoduction.

John is correct that the ITU speaker is what SACD and DVD audio expect.
DVD movies (Dolby Digital, DTS, DPL-II, and THX etc.) do NOT.

The room itself determines whether 5.1 7.1 can be optomized and if they make sense.

Remember that 7.1's goal is to make the sound track of movies most enjoyable to a wider group of people (more / multi-row) in the listening environment. It is not primarily to increase the enjoyment of the "sweet spot". It also opens the palette of sound effects and panning effects for both muti-channel movies and music. It does not however decrease the sweet spot, it is the other things, like John discusses with speaker placement that effect those sensations.
 ...

Hi Scott,

Long time no see.  

Glad you saw the "take home" message I was trying to convey.  As all the Audio and HT processes continue to develop it will become harder and harder to address them with a single system or room.

In most cases one will have to give priority to the processes.  In my case it would look like this:

1) 2 channel or 3 channel Audio

2) 5.1 or Multi channel Audio

3) 5.1/6.1/7.1 HT

I still think that the most difficult and precise sonics are in 2 channel audio.  I personally am not moving into 5.1 Audio until the system is a little more "buttoned down".

And as I mentioned earlier since Movie Sound is never "REAL" (unless it is your home movies) it seems to be the area that can take the biggest hit of "compromises" and still offer great sonics and entertainment enjoyment.

[Housteau]

Since the ITU speaker  standard was mentioned a few times, I thought I would research it a bit.  I came across this Telarc site:

http://www.telarc.com/surround/sacd.asp?mscssid=6R9T8V245HSR2P270G05AFURQEAJ25F3#loudspeaker

It has some decent explanations for audio set-up, both for SACD and DVD-A.  I found the part about the optional height (side) speakers interesting.  Apparenty some recordings use that .1 channel to express a height image to the illusion instead of a subwoofer channel.  So much for the standard I guess .

I can see Julian's point about the listener being placed more centered within the room and not ideally for bass response.  I guess the answer to correct this would be to extend the wall behind the listener, so that spot would no longer be the center of the room.  Julian mentioned a possible room length around 30' would be minimum.

That places a lot of space behind the listening seat with the listener actually closer to the front wall to get out of that bass null.  I have never been in a room set-up quite like that.  Have any of you and how well did it work?  I am used to being closer to the rear wall.

Dave

[James Romeyn]

I so admire Julian for jumping into the TriN waters & spreading the gospel.  I have heard many expensive audiophile grade HT & multichannel systems.  I heard the TriN at CES & at Brian's on X & 40s.  Though the 40s & X are superior to the speakers in the HT & MC systems auditioned, I am convinced that Julian is right: TriN kills HT & MC technology.  HT/MC are generally just more of the same.  TriN is a completely different experience.  As soon as I can replace my Elite with a projector & perforated screen, I am joining the party: custom X cabinet in the center (minus the swooshes) flanked by 626Rs, an A2K for the center & a stereo Ampzilla for the flanks.

BTW, an acquaintance has five Academy Awards on his TV, for movie sound post-production (prefer to not say the exact field).  Pease don't repeat this, but I thought the TV sound at his house was well, pretty bad (we heard a portion of T2, he had only 3 Academy awards then).  I sure hope ears with different priorities are involved with Multichannel, otherwise it is doomed.