several questions about WDST

[STL]

Are Klipsch WDST surround speakers made to me mounted on side or back walls? I suspect they are really made for side-wall mounting, but how well will they work for back-wall mounting (in terms of surround sound for DD5.1 and DTS movies)?

Did Klipsch ever make a WDST speaker with a single horn in the center and two woofers (each firing away at different angles)?

Since my HT system primarily showcases DD5.1 and DTS movies, would WDST surrounds really be the best choice or would 'regular' Klipsch speakers be a better choice for rear surround?

[WMcD]

To my knowledge there has not been a single horn version. The design is that each horn handles about 90 degrees of arc and the two cover 180 degrees together. There was a dual woofer version.

I don't think it is a question of whether they will work on a back wall, they certainly will.

A better question is where any "surround" speaker set should be placed. Particularly when the size and shape of the room comes into play.

Very generally, surround sound theory put the two surround speakers to the listener's left and right flank. 90 degrees from forward. They can be moved about 20 degrees forward or back from there. Not really a quad set up.

Exprimentation with placement is often required for best results in a given room. This is because of acoustics or just where you might have a wall.

There is a trend to 6.1 channel sound. That puts a third surround speaker someplace between the flanking surrounds to fill up the gap. So it is usually going to be on a rear wall.

Would it be "better" to use the same speaker type as the front units? Conventional theory is no.

Theory ONE is that the "surround" speakers should have a design so that the sound can not be localized. I.e. seem to come from a specific location. The WDST design spreads the sound around so that it seems to come from everywhere. Therefore it is "ambiance."

Theory TWO is that the frequency output of the surrounds should match that of the front units. This is because a lot of sound effects is not ambiance, but a real source (car, jet) which pans from front to back or back to front.

As you might imagine, this is a bit contradicatory to Theory ONE. But Klipsh uses the same or similar horns in the mains and surrounds. So things work pretty well.

People have reported good results having identical speakers all around. This may be working better when you're thinking of the panning versus ambiance types of effects.

From my reading, no one has ever said there is a single optimum solution.

Gil

[HornEd]

STL, you have hit on what is a key issue... building a system for yesterdays surround technology or building a system for today and beyond. Klipsch WDST technology is an attempt to make the best of an awkard situation and bridge the gap of having what breaks down into two systems of multi-channel (i.e., beyond two-channel) recording. Many of us are exploring ways we can get better results.

"Surround sound" and discrete center channels existed before Dolby ProLogic caught on. The rear channels were fed primarily narrow frequency mid-range "auditory clues" that blended with the mains, center and subwoofer (in a better system) to provide a sense of orientation within the sound envelope. What I refer to as auditory clues were more localized than the more ethereal "ambient" sound in the Dolby ProLogic approach. In the early surround approach, there is not enough information in these surround channels to warrant ultra high speakers.

The newer "discrete" surround and rear effects approaches tend to use a more robust frequency spectrum with the trend to having a full spectrum that may be called upon for greater realism. This is where timbre matching can become a real issue. If a tank rumbles from the rear of your HT to the front screen, you would like its characteristic sound to be the same from the rear effects speakers, to the side speaker, to the main speakers. On most systems, this is not the case because the side and rear speakers are usually not as robust as the mains.

WDST is an attempt to have a woofer firing directly toward the listener to handle the "discrete" programming and two 90 degree horns to provide the "ambient" effects. Since discrete programming can be proportioned between discrete speakers, an ambient aspect can be matrixed into the surround and rear effects speakers. Obviously, the WDST approach handles this aspect quite well.

While WDST speakers make a noble attempt to be all things to all people, to date, they fall short in providing the timbre, sensitivity and character of the main speakers... a factor that should become increasingly important as new DVD's are released with sound engineers targeting the full potential of 5.1, 6.1 and 7.1 systems. The problem with most side surround speakers is the same as with many attempts at finding the right center channel... the "same sound" that travels from one speaker to the next does not sound like the "same sound!"

I have tried several surrond configurations, including WDST, and found that using the same side speakers as the mains is much preferred (in my case KLF 30's). I would like to have a speaker with a pair of opposing mid-range horns that match the KLF 30 that could be placed atop the KLF 30 to augment the "surround" aspects of older DVD and cable fare.

On balance, I would rather build my system for today and tomorrow by using duplicates of the mains for side and rear effects speakers. Having an amp that plays 6.1 straight and matrixes 6.1 from 5.1 material is a distinct advantage. Having two side speaker and one rear speaker that match the mains creates a "diamond shape" similar to the way most diamonds are cut to reflect a greater amount of light. For HT, that is two mains close to the screen, ceter above, sides further apart and faced toward listener, and a rear effects on the back wall. This provides a good fill for sounds that transcend one or more speakers. It costs more, but especially with Klipsch speakers, it delivers multi-channel music and DVDs with gusto! HornEd

PS: The rapture of music a two-channel audiophile system is a whole different issue... but slumming with a good 6.1 matched speaker system can bring more musical joy than you might imagine.

------------------

"HornEd Herd"

Front Six Pack:

KLF 30's R&L + KLF C-7

KSW-15 Sub, SB-2 Effects

Side Surround:

KLF 30 on KSW-12 L/R

Rear Effects:

KLF 10 L/R

Rear Center:

KLF 10 atop KSW-12

Speaker Support Systems:

Mitsubishi RPHD1080i 65"

Yamaha RX-V3000 Receiver

... and counting!

[RossVTaylor]

STL,

Gil's reply is, as usual, thorough and dead-on accurate. I might only dare to add that, although the preferred surround placement is as Gil noted, there are some times when the room won't permit ideal placement. One nice thing about the Klipsch wide-dispersion setup is that, in a pinch, the speakers allow a great deal of flexibility in placement. Their very wide dispersion pattern even works with one surround placed on a side wall and one on a back wall (not ideal, like I said, but they can overcome room placement obsacles like windows or arches). You could even place them on the ceiling over your head, pointing straight down, if you had to (mounted with the horns front-to-back, if you can picture that). You don't have this flexibility with with dipole speakers with a null area.

As far as the second question goes, most people seem to prefer WD speakers for HT and direct radiating speakers for music. Some receivers and preamps even permit both options. I've got four RS-3's (two side and two rear) for HT, but two Heresy II's for music surrounds. My stuff's not yet installed in the new room, but that's the plan anyway. Since you're primarily a movie watcher, I'd go with the WD surrounds.

Best of luck,

Ross

------------------

"Time flies like an arrow.

Fruit flies like a banana."

[RossVTaylor]

While I was writing my "go with the WD surrounds" response, HornEd must have been writing his "go with point source surrounds" response. I don't mean to sound like I was contradicting him intentionally!

I'd love a room with matching speakers all around, but there's no way I could fit it. This summer, in Hope, we spent some time in the Klipsch theater room. Like HornEd said, there's something to be said for lots of "traditional" surrounds. The Klipsch room had eight Heresies (what is the plural spelling?) as surrounds... ahhh. Nirvana... But, in my meager media room, I had to make a compromise. I've got LaScalas up front with a Heresy II center. The RS-3's, although not a perfect tonal match, sound great with the front speakers on HT stuff. In most cases, it's more important that the front array of L-C-R speakers match tonally. There's some leeway on the surrounds. I still think you'd be very happy with the WD speaks, but YMMV.

I'd make the usual "try out both and see what you like" suggestion, but that's not always possible when your'e talking about multiple surrounds in your particular environment. Tough spot to be in... You could always go with a pair of WDST's for HT and add a set of directs for music. Or you could go with directs, and if you didn't like them you could put them in another room. Of course, if these are the toughest choices we're faced with then we are truly lucky!

Ross

------------------

"Time flies like an arrow.

Fruit flies like a banana."

[STL]

quote:

---

Originally posted by William F. Gil McDermott:

Theory ONE is that the "surround" speakers should have a design so that the sound can not be localized. I.e. seem to come from a specific location. The WDST design spreads the sound around so that it seems to come from everywhere. Therefore it is "ambiance."

Theory TWO is that the frequency output of the surrounds should match that of the front units. This is because a lot of sound effects is not ambiance, but a real source (car, jet) which pans from front to back or back to front.

---

As I understand it, Theory ONE bascially applies to matrixed surround (like Dolby Prologic) while Theory TWO applies to the newer discrete surround (like DD5.1 and DTS). I have been doing HT for quite awhile, so I have good understanding of the different surround sound techniques -- but since I don't have any WDST speakers I am trying to learn more about them (and I couldn't find a lot of specific info about the WDST concept on the Klipsch website).

I have a pair of KG5.5s for front mains, and I bought a lone KG4.2 that I will re-box and use as my center (which should be a good match since it has the same tweeter as my 5.5s). I also have all the drivers (and xovers) out of a pair of KG4s. I plan to build an enclosure for them and use them as surround speakers -- so I was trying to decide what type (WDST or not) of box to build for them.

[STL]

Thanks HornEd and RossVTaylor for the info, but I already have a pretty good background in surround and HT (but your information was very decriptive and will no doubt help future newbies who read these threads later). I'm just not real familiar with Klipsch's WDST design and it's real intent. I suspect it is trying to achieve some ambience like di- or bi-polar speakers (and would be more of a compromise for a discrete surround sound setup). As I mentioned above, I have the parts from a pair of KG4s that I will be building a enclosure for them, and I was trying to determine whether to build a WDST-type box or a regular box. Note these speakers will be installed in a built-in bookcases on my back wall of my room (so a WDST isn't looking like a good idea now).

On a tanget, I honestly don't see the need for 6.1 surround (at least not with Klipsch drivers). My KG5.5s, just in stereo mode, setup such a good soundstage that it often sounds like I have a center channel playing! The fact that Klipsch horns stage so well and that a 6.1 mandated center speaker(s) would be directly behind the listen, I do not see how a listener would be able to really discern a true rear center speaker. It would seem that two properly driven (discrete type) rear surround speakers should easily be able to fool the listener into thinking there is a phantom center!

[STL]

quote:

---

Originally posted by William F. Gil McDermott:

To my knowledge there has not been a single horn version. The design is that each horn handles about 90 degrees of arc and the two cover 180 degrees together. There was a dual woofer version.

---

Thanks for the info...that's what I was thinking too.

[boa12]

guess u could always put 3 directs like the klf-30 at the appropriate angles on each rear corner or side wall

whoops, hope horned didn't hear that for his pocketbook's sake

------------------

Klipsch KLF 30 (front), KLF C-7, Cornwall I (rear)

Velodyne HGS-18 sub woofer

Monsterbass 400 sub interconnects & Monster CX-2 biwire & Z-12 cable

Marantz SR-8000 receiver

Sony DVP-C650D cd/dvd player

Sony Trinitron 27" stereo tv

Toshiba hi-fi stereo vcr

Technics dual cassette deck

Scientific Atlanta Explorer 2000 digital cable box

Boa's Listenin Lounge:

Klipsch RF-3 (front), RC-3, cheap little Technics (rear)

Monster MCX Biwires

Sony STR-DE935 a/v receiver

Kenwood KR-9600 AM/FM stereo receiver (vintage 1975)

Russound AB-2 receiver switch to RF-3

Teac PD-D1200 5-disk cd changer

Technics direct drive turntable

Sega Genesis game player

Sub: None yet

rock on!

[HornEd]

As you might suspect, Boa, I have been experimenting with the three KLF 10's in setting up direct rear effects. Of course, the method chosen by the sound engineers (and not revealed in so many words on the jacket) create a huge difference in how the sounds can be made to come across by the choice of speakers and placement. This is particularly true of those of us who like to do it "discretely."

Which leads to STL's theorizing about the adequacy of a phantom center. In my setup, a 5.1 source becomes a matrixed 6.1... and a less than 5.1 source comes across at least as a 5.0 with the actual center falling silent and a "phantom center" imposed by the surrounds. Let's face it, nearly all of us are using Klipsch speakers and if the source material is good the Klipsch speakers are going to make it good... but a real Klipsch rear effects speaker beats a Klipsch induced speaker hands down. A good 6.1 DVD (even if it is 5.1 matrixed to 6.1) brings an extra measure of pleasure.

Now, years ago, I used an upscale phantom approach over a true center approach because I was using a huge projector filling an 18'x9' screen and I was trying to reduce "directional sound gaps"... and it worked. But, today's creative sound engineering migration seems to be toward more discrete rear sounds and a greater attempt consciously blend background sounds for discrete dissemination.

If the WDST technique that Klipsch employs with quality speakers were the norm, I think the migration to discrete speakers would be slower. However, it should be noted that creating an "ambient" background sound is a lot easier and cheaper than building a real discrete sound showpiece. Sadly, a lot of reissues of old films in 5.1 formats take the cheaper course. I thought "Ben Hur" fared better than "Lawrence of Arabia" on that score... even though the sound tracks of "Lawrence" had been lost and the principal acters had to lip sync there lines many years later.

STL, if you get a chance, sit through the best parts of a good 6.1 DVD in a good 6.1 speaker environment and then listen to it on its 5.1 option using a phantom channel. I think you will find, as I was surprised to find, that there is a distinct "gut level" difference in enjoyment.

As ... theory may sell speakers... but its ears that make them keepers. :ears (oops, they don't have that smiley yet!) HornEd

[STL]

quote:

---

Originally posted by HornEd:

As ... theory may sell speakers... but its ears that make them keepers. :ears (oops, they don't have that smiley yet!) HornEd

---

I guess I need to do that. I can see how using a phantom center for the front setup would be less than a 3 speaker setup, but when it comes to the rear I just cannot see how it's really needed. Heck, human ears are built to primarily gather sounds from in front; I would think people would have a hard time determining the presence rear center speaker in a blind test. Having said that, I will go listen to a setup just to see how it sounds, but I wonder if these 6.1 soundtracks are adding something more (than just additional rear center information) that may be clouding the issue. Right now I still feel 6.1 is more of just a marketing/sales ploy.

[HornEd]

Yup, I understand your point of view... and shared it when I bought a receiver for features other than its ability to do 6.1 which I viewed as a "moneysucker" feature. So I backed into 6.1 with a negative attitude toward it. Shades of STL!

Obviously, our eyes and ears are mounted as predators... and our program material is structured to attract the full frontal attention of our natural predator config. I mean, if we are fully rapt on what we are devouring... what need do we really have to divert our eyes and ears from the movable feast before us?

Ah, but there is more to our sonic jungle than meets the eye. The sensation that there is a world behind which you cannot see... but only here and feel... in the hands of an enlightened team of creative sound engineers... the total immersion of the sonic jungle does not have to be lost in "boob tube" fixation.

In the early days of surround sound experimentation, multiple speakers were used to emit verbal clues not unlike the sonic reflections of a good listening hall. Yamaha (and others) have long tried to achieve that with DSP chips... much maligned as purists have made them.

But the fact remains, as predators, that sound that is located directly behind us has the potential to be the most ethereal... and is made less so by the amount that is available to side speakers. What I am trying to portray, in my less than eloquent prose, is that the "drama of sound" can be better engineered with a 6.1 system rather than a 7.1 or 5.1 system.

It follows, of course, that a 6.2 system would be even better... with a rear subwoofer located 180 degrees behind the "primary ears" of the household. The reason being that the low end of directionality tends to arouse the primal sense of another presence that cannot be seen... and which is better developed in lower prey animals.

Don't shortchange your Klipsch config on its course to develop a deeper appreciation and joy beyond sales hype. I got to go turn on some "New World..." HornEd

[KGeist]

On a tanget, I honestly don't see the need for 6.1 surround (at least not with Klipsch drivers). My KG5.5s, just in stereo mode, setup such a good soundstage that it often sounds like I have a center channel playing!

Yes, but only true along the axis of symmetry between the two loudspeakers. Move off to one side and this effect disappears (It also dimminishes with distance). For this reason, it has been said that stereo is an "antisocial" medium (only one person can really enjoy it). A center channel stabilizes the center image so that more than one person can enjoy an accurate sound field. This is also true of the surround speakers and is the primary force driving 6.1.

A Multi-channel system simply provides more points from which sound can be made to appear. The stereo effect in multi-channel formats can, and is, still used effectively to position sounds at points other than the speakers.

Kerry

[PhilH]

The ideal situation with surround sound speakers would be several matching speakers (same mid/high drivers as the FL and FR) lined up in the rear and on the sides to produce ambience through some/all of the speakers using a multi channel configuration. This "sound wall" setup would also lead to ideal localization of sounds in the rear using one or two, etc. of those speakers and channels to project a localized sound, such as a gunshot, into the audience. Custom movie theatre systems come as close to this ideal as possible, due to the available room allowing mounting of multiple larger speakers combined with a multi-channel soundtrack.

In real life, we have a different situation at home. Most of us do not have the room (or money) to place several equal speakers (equal to the fronts) on the side and rear of the listening area. Also, 95% of the multichannel software and hardware we have to work with is 5.1 information, allowing just two channels to operate in the rear. This is an advantage though over older systems, such as Dolby Pro Logic (should we now put a 1 after this term?) which had a limited bandwidth, mono channel for the rear. Narrow "ambience" was the only real possibility from this system, and THX later used bipole and dipole speakers to widen this ambience.

With today's DD and DTS 5.1 information, the engineer of the soundtrack has the ability for both ambience AND localization by using the rear two channels both together and separately. For this reason, the best surround speakers (especially when one is limited to 2 speakers for the rear or side) for the home should be able to incorporate both of these characteristics. Our WDST speakers are excellent producers of both sounds needed for the rear channels. As Gil said, the dual 90 degree horizontal radiating horns in each speaker combined give 180 degrees of ambience (and do not need a long length of wall on both sides to "bounce" the sound for the best ambience as some multi "pole" surround speakers do). With the same speaker, the "controlled directivity" of the horns also produce good localized sounds. In other words, speakers, like Ross said, that have VERY flexible placement options (unlike the bipoles and dipoles) due to both their size (in comparison to speakers matching large front speakers) and their ability to produce ambience without needing some wall space to bounce sound off of.

For 5 channel music, a non-surround type of speaker is preferred. Of course, more and more receivers today are allowing hookup of two sets of side/rear speakers for that purpose. As time goes on and technology moves forward (more DD Ex and DTS EX and newer formats), I'm sure we'll see additional channels for HT for the side and rear area, making the need for a dual-purpose speaker less and less (for those that have the room). Until then, our WDST models have the flexibility to fill the current need.

[HornEd]

Well said, PhilH... but I still prefer DTS 6.1 program material to bring out the psychological benefits of sound that may move closer to art than engineering. All too often, explanations with engineering precision fall short of the consumer's "sound art appreciation" in the real world.

As in other posts, I have loudly applauded Klipsch for it's WDST approach to bridge gaps in recording formats and keep my ears open to future iterations.

I appreciate your leaving room for tomorrow's innovations, for if the solution of any given day were all that compelling, there would be no need for such a long list of "Classic" Klipsch speakers with the admonition, "While no longer in production, (fill in the blank) model loudspeakers are still owned and listened to by Klipsch fans around the world as part of home theater surround sound systems.

Klipsch has groomed us to probe the envelope of sound and senses... and, thereby, encouraged us to make the money it takes to seek and enjoy our individual audio paths. And we thank you for it! HornEd

PS: Thanks for leaving some room for those of us who buy multiple Klipsch speakers to explore "sound walls" as we may. Klipsch has groomed us to probe the envelope of sound and senses... and, thereby, encouraged us to make the money it takes to seek and enjoy our individual audio/art paths. And we thank you for it! HornEd

PS: Thanks for leaving some room for those of us who buy multiple Klipsch speakers to explore "sound walls" as we may.

This message has been edited by HornEd on 05-25-2001 at 09:15 AM

[WMcD]

I may venture a guess at the way things are going.

Let's look at the "surround" situation as being just a situation on the front wall, rather than the rear. This is just for the thought experiment.

Situation One: You have a mono signal. This is what early Dolby was as far as a source of the surround signal. You want to make it sound like a wall of sound from everywhere: Having two widely spaced speakers which have wide dispersion pattern fed with that mono signal would work fairly well. There would be reflections around the room.

Situation One is the "old" 5.1 Dolby. It only had a single source of surround sound. It was up to the speaker wide dispersal to spread sound around the room. There is not too much to play with given a single source of program material.

Situation Two: You now have three signal sources for "surround" to work with, and three speakers. Now there is a lot that the mixing engineer can do. Playing with amplitude, phase, and delay, the apparent sound source we hear can be fixed at from center, right, left, or from no localized position. We hear such effects in a "actual" three channels in front system.

Situation Two is the newer surround systems with discrete multi channel surround.

In Situation Two, the wide range of effects are accomplished in the mix. It would be best if the corresponding surround speakers are not wide dispersion. Rather, the same tight focus which allows best performance in the front three channels can, and perhaps should, be used.

The job of creating "ambiance" or (on the other hand) discrete sources is up to the mixing engineer. The engineer can accomplish either.

However, while ambiance can be accomplished with multi channel feed and narrow dispersal speakers, single apparent sources can not be as well accomplished with wide dispersal speakers, even if there are multi channels of source material.

This may be why narrow dispersal speakers are better for multi channel surround. It is the same as why they they are better for the front.

Now I have a question. Suppose you have a 6.1 receiver with three surround but fed by a 5.1 source, like a VHS tape. Does the receiver have a setting to compensate so that the mono surround is synthesized into ambiance across the three rear channels?

Gil

This message has been edited by William F. Gil McDermott on 05-29-2001 at 01:19 AM

[HornEd]

Gil, it is always a pleasure to read your engineer's crisp and accurate replies. Obviously, maximizing the sound illusion between ones ears is always a challenge of infinite variables... but this "ambiance" vs. "discrete" aspect can be particularly trying.

The answer to your above question is a resounding yes in the case of a Yamaha RX-V3000. 6.1 material is played as 6.1... but 5.1 is played as matrixed 6.1 creating exactly the blended rear sound wall that you surmise.

Frankly, Gil, I am hard pressed to change receivers or go to multiple separates for HT at this juncture because this particular Yamaha slides between converting stereo to 5.0, 5.1 to matrixed 6.1, and 6.1 as 6.1 without intervention... and having six KLF 30's strategically placed (plus subwoofers at low xovers... but that is another issue) creates a particularly enjoyable HT experience... without annoying tone and timbre shifts on back-to-front pans, etc.

I should be noted that in rooms that are sufficiently wide, a side mounted KLF 30 does an even better job as a "surround" since the exponential horn covers a wider area. In their present location and given the room size, I am toying with building a separate box containing two matching KLF 30 horns covering a 180° arc to better enjoy older program material.

Having a comprehensive rear sound wall that matches the mains seems to create an improved sound environment not only for me, but has increased HT enjoyment for my dementia afflicted 93 year old mother... for whom this system was designed.

On that note, I should add that the front sound wall is also enhanced by mounting a KLF 30 horizontally above the RPHD 65" Mitsu (after replacing the board with the horns mounted horizontally between the woofers) to replace the KLF C-7 (a great center speaker!) to reduce the effect of tone and timbre shifts in left-to-right pans, etc.

One last benefit from this particular Yamaha stems from its separate amplification of front effects speakers... which, in effect, creates a high and wide front sound stage (I use Klipsch SB-2's on 6' high sand weighted columns placed 3' outside of the mains and angled toward the primary listening area). This allows the mains to be close by the RPHD1080i monitor for better dialogue orientation. It is interesting to watch the same passage with and without the front effects turned on. In almost every case, the effect is richer with the effects on. A word of caution, however, good front effects need to be carefully set using an SPL meter to achieve their best value. In essence, they create a muted, ethereal sonic background and allow the mains command of the center stage.

I have used this system to illustrate converting a less than ideal 14' x 24' space into a worthwhile HT environment during a period of shifting sound mixing technologies. The KLF 30's were selected for the character they bring to an HT set up... and I suspect that the new "7" series might be even better set up this way. All-in-all, it is a continuing search to engineer HT with focused intensity and psychologically comforting sound walls.

For two channel music, I prefer other Klipsch and amp/preamp configs... but that, too, is another story.

Thanks again, Gil, for all your informative and well meaning posts. I admire your economy of words and your continued attempts to encompass broader ranges of variables than many others use in their opinions. You have earned a "Gil fan" base in the best possible way and give credence to this board above and beyond its Klipsch commercial orientation. Thanks. HornEd

------------------

"30 Something 6.1 Herd"

KLF 30 Mains

KLF 30 Mod Center

KLF 30 Mod Surrounds

KLF 30 Rear Effects

SB-2 Front Effects

Subs: KSW-15 + 3 KSW-12's

Speaker Support Systems:

Mitsubishi RPHD1080i 65"

Yamaha RX-V3000 Receiver

and more...

... UNDER CONSTRUCTION!

This message has been edited by HornEd on 05-29-2001 at 07:29 AM

[STL]

quote:

---

Originally posted by William F. Gil McDermott:

Suppose you have a 6.1 receiver with three surround but fed by a 5.1 source, like a VHS tape.

---

I am not aware of any VHS tapes that offer a 5.1 audio track! I thought the best a VHS tape could do was Dolby ProLogic which is only 4 (matrixed) channels. Was this a mistake or did you really mean what you said?

[WMcD]

Aww Shucks. What can I say. It is tough to gauge when one's own input to the debate is worthwhile, or just running at the mouth. Sometimes I wonder if I write too much or too little. I do work at clarity and accuracy. So I'll take your comments as a reason to continue.

Actually, you'll note that Phil H. had many of the same comments stated in a different, perhaps better, way.

HornEd, you're a remarkable guy to find a creative way to keep your mom enjoining life via your hobby and enjoy it together. I'm sure it is challenging and rewarding. God bless.

My motive was to give some explanation of the entire system of hardware and software which ultimately delivers sound to our ears. It came out a bit backwardly. When my boss says, "let's go back to basics", I cringe. We know this stuff. But such discussion can isolate the real basis for points of debate without getting lost in the jargon.

I'm setting out things below to integrate some technical matters discussed above, and trying to put everything on one sheet of paper for the benefit of new readers.

Going through the chain we have:

(A) Mixing by the engineer. What the studio engineer can accomplish at the distant home end is determined by all that follows.

( How many channels are available for storage/transmission on tape, CD, DVD, radio, TV, even vinyl.

© How much processing power is available in the receiver. How can it extract information given (.

(D) How many speakers are available in the listening room. How do they interact with the room itself, and where the listener is sitting.

The overall challenge is that (, ©, and (D) are variables in a given hardware situation at the consumer level. I think it is fair to say this an ongoing "problem" or "issue".

Borrowing from the computer industry, how can all systems be made backward and forward compatible, in all platforms? What is "best" today (nothing is best for all things), and how did we get into this mess?

At the beginning of the surround sound era, there were few channels ( and elementry processors ©. So wide dispersal speakers or dipoles (D) were envisioned to make up for shortcomings.

Later the trend was to better processors (e.g. pro-logic and decorrelation).

Then there came to be more discrete channels available in the storage media (DTS). So there was not as much reliance on electronic processing at the home end © and dispersal (D), it could be done at (A).

However, as Phil H points out, not everyone has DTS or wants it. Also, we have "heritage" types of media. So, advanced home hardware HAS to simulate old types of hardware which was assumed by the engineer when the mix was put down. Better yet, let's just admit (quietly) that five or ten year old software technology IS what we listen to for the most part.

- - - - -

STL, correctly, points out a faux pas on my part. It is a problem of nomenclature which is vexing.

Some months ago I proposed that "5.1" is, strictly, a speaker set up, (D) above. We have, counting, left surround, left main, center main, right main, right surround (that makes 5) and a subwoofer, which is the 0.1. I got some flack and dropped it. But I'll stick with it here.

When we have a 6.1 system, the added integer is for the center surround speaker.

This speaker nomenclature doesn't suppose to tell us about the storage/transmission channels (. That is another issue.

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Whoops, so what is that issue?

As correctly pointed out by STL, VHS tapes have only 2 discrete channels (B above). From that, the processor (C above), creates 4 "matrix" channels. Phil H. points out that this is the majority of our listening, so let's review.

The process is:

and

, and

,

. The information is further processed with a delay and other stuff, like Dolby noise reduction, frequency limiting, and then sent to both Left and Right surrounds. Therefore, the L-R signal is sent to two surrounds. This is how 4 channel matrix turns into 5 speaker outputs. We're doubling up on the rear speakers.

The remaining processing is to the subwoofer. Not a matrix of adding or subtracting. It gets simply the bass from the two inputs. Again, this is the 0.1.

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Please forgive the redundancy and restatement in a different organization. Now I feel a bit more comfortable that things are set out as one grand theory in one place.

Regards,

Gil