Stereo versus surround sound

[maxg]

"As for the hole in the middle in stereo sound, unless you sit dead center and don't move your head even a fraction of an inch, you can almost always pick out the source of the sound as being two loudspeakers"

The degree of head movement allowable retaining the soundstage varies with speakers, room, distance from the speakers and so on.

In fact the size of the sweet spot varies dramatically with speakers in any given room.

For my setup you will get a strong centre image within about a 4 foot radius of where I sit. Moving outside of that leads to a gentle movement of the centre image towards the speaker you are nearing upto the point one speaker is dead ahead and all the sound seems to be coming from that speaker. YMMV

[skeptic]

Speakers with excellent high frequency dispersion and plenty of nearby objects to reflect those frequencies create many paths for them to reach the listener and therefore make it more difficult to identify the exact source. But is is impossible for two loudspeakers to reproduce the effect of 100 or more individual sources spread across a performing stage. And it is also impossible for 4 or 5 loudspeakers to recreate the auditory effect of the carefully designed diffuse reflective properties of a concert hall that took tens of millions of dollars to design and build and years for acousticians to tweak no matter what signal is fed into them. The human ear and brain are just too good to be tricked that easily.

[Sir Terrence the Terrible]

There is only a few times in my posting history that I have seen so much misinformation that really stands correcting. Let me jump into this..First, Skeptic you are so on the mark that its not even funny, you raise some excellent points. Let me address one point.

[quote]I tend to agree with others here that the biggest problem with surround sound (on the above 2 media) is that engineers have still not got to grips with it. I have about 15 SS SACD's and the results are VERY variable.[\quote]

The reason for this variablity has nothing to do with the engineer, it has way more to do with the content that he(or she) has to mix. Mostly all SACD's released(and this goes double for classical music)has been reissues who's master tapes are of variable quality. You can only do so much to clean it up, eq it, and process it to make it suitable for the format. The releases that have been done with multichannel SACD in mind are of exceptional quality, and when heard on a quality system this cannot be argued.

[quote]As for the hole in the middle in stereo sound, unless you sit dead center and don't move your head even a fraction of an inch, you can almost always pick out the source of the sound as being two loudspeakers unless those speakers disperse their sound by reflecting them off a large surface. That is for the same reason you can pick out the location of the auxiliary speakers in a surround system. [\quote]

This is not true at all. Speakers that are time and phase correct will produce the exact waveform that is fed into it. That means both the direction and amplitude(this coincides with information from Skeptics post) Unless the microphone technique employed is flawed(or the speaker is suffering from severe beaming), the speaker will not introduce the hole in the middle effect at all, and if it is accurately performing it will do a reasonable job of recreating the entire frontal hemisphere in terms of soundstaging with a high degree of transparency. Accuracy is the key here.


[quote]Well for one thing if you are listening to DD5.1 or even DTS you are listening to a highly compressed file format. If you have DVD recording software - check out the file sizes when you use any DD format and compare it to using plain old PCM[\quote]

File sizes when talking about compressed audio is irrelevant. MLP(Meridan lossless packing) can compress a audio signal down to 1/3 of its normal size without any losses. While DD is not transparent at any of its data rates, Dts at 1.5mbps can do an extremely credible job of coding a signal with minimal loss of transparency. Dts 24/96 can code without any loss whatsoever. Considering how a compressive codecs work(DD is very extreme and cannot be used in this example) the only data that is being discarded is redundant and inaudible signals. What is left is being encoded at 20-24bit word depths(engineers choice). PCM is not a very efficient carrier of audio signals as it contains both redudant and inaudible signals alike.


[quote]Most players are not capable of playing it back in native form (actually most recording software isnt capable of creating it either - my current problem) - but some are - worth checking out next time you buy.
[\quote]

Most CONSUMER software is not able to record 24/96khz audio but professional software(protools specifically) can work with 24/192khz signals with any loss whatsoever.


[quote]The funny thing is - that 96/24 recording ability is only available in 2 channel LPCM format - and according to the original specs - for high quality music. In other words if you want to listen to really good quality music do so in 2 channel mode (according to the orginal designers of DVD that is). [\quote]

24/96khz is available in 5.1 DVD Audio. 24/192khz is only available in two channel not because of the recording technology, but because of the limitations of the DVD spec itself. It is only able to handle 9.8mbps which is not a high enough data rate to support high bit, highly sampled audio.I think you are mixing up the standards for CONSUMER recording with the standards of professional recording.

[quote]Take a look at the specs for THX - this uses different types of speakers for centre channels and for rears.[\quote]

THX standards only apply to movie sound, not high quality music. To even mention THX in the same sentence as high quality audio is a huge mistake. All THX systems having matching front speakers but use dissimular rear speakers, that doesn't make them bad for music, just not optimal


[quote]The second problem is speaker placement. According to Sony the speakers should describe a circle around the listener and be in the same virtical plane - according to the THX standard you have effectively a flat line of speakers at the front and the rears should be closer to the listener (and I think - above them - firing down)[\quote]


I think you need to take a second look at the THX standards. They have now been revised to reflect timing issues in regards to speaker placement. Sony is not who I would go to about speaker placement. Anyone who recommends that the surrounds and the front speakers should be on the same plane is insane. Any sound arriving from the front and from the rear simultaneously will totally confuse the ear/brain operation. The rear speakers should ALWAYS be elevated above the front speakers for just that reason. 99% of all recording studio's elevate their rear speakers for just this reason. THX does not recommend having the surrounds closer to the listening position than the fronts, they now recommend equal distance.

[quote]This recording was put together by a company called Q-sound. I have no idea how they have done it - but you will find voices and effects coming from behind you!! Scared the pants off me the first time I heard it at home - I thought someone was coming in from the balcony doors.
[\quote]

You are not hearing a fully mapped soundfield in this process, you are hearing signal fed to the front channels with vector crosscancellation processing applied to reduce crosstalk between the ears. This is NOT surround sound nor is it a FULLY mapped soundfield. They do it by applying a little bit of the left channel information into the right speaker out of phase to cancel the effects of head related transfer phenomina which can truncate the front soundfield. Polk use to use the same process on their older(and no longer made) SDA series of speakers. This is old technology and totally unecessary with DVD-A and multichannel SACD out there.

[quote]3. Vinyl is compressed.

Well it can be - but it doesnt have to be. Try a classical recording from DECCA on one of their Full Frequency Recordings, or even Dutch, Philips recordings from the 1970's onwards. Alternatively (and I hate to recommend audiophile recordings - [\quote]

All of the records you mention are very good sounding indeed but compressed because they are limited by the recording technology of the period, or the format itself. If you made any attempt to master vinyl records with the dynamic range found on today's recording, the needle would jump off the record and kill you!!
Also the headroom on older ampex recorders(Decca used these on their full frequency series) was not typically very high, so gain riding was a common practice in those days.

[quote]I am perfectly happy living in the dark ages with LP's and other forms of two channel stereo. Many other people must be too or they would not still be making turntables that sell for 1.5k (for a midgrade high ender) to as much as 85k, or cartridges that run into several thousand. The most expensive amplifiers that I know of are either monoblocks or stereo amps and can run right up to 100k or so for a stereo pair. Does that equate dollars to sound, not necessarily but someone must think so and I don't think they'd shell out all that money for a 5.1, 6.1 or 7.1 receiver. I know I wouldn't.[\quote]


I didn't think that anyone would buy an air conditioned dog house advertised in the Sharper Image several years ago, but people did. I didn't think that people paid 20k for a vintage car that would just sit in the garage, but they do. I was floored when I found out that men PAY for sex, but they do. People pay for what they want, but that doesn't necessarily mean that its a superior product. The fact that a person would pay from $1500 to 85k for a turntable does not mean the vinyl format is superior to those small shiny disc, it just means they are willing to pay top dollar for it good or bad. I think now that we know that the most expensive turntable with the most expensive cartride still creates distortion during playback(regardless to how clean it was mastered) shows that some people like distortion more than others. Another point is that there are no receivers on the market that costs $100k, and if there was, somebody would buy it just to say they own a receiver that costs $100k. That would certainly represent a better value than just amps that cost that much.

[RGA]

Sir Terrence

If SACD is typical(and I know it's not) like what I just heard today and what most average people hear then they may as well give up now and forget the whole thing. I have heard better but this rather big chain in Canada had the Denon 2200 DVD/SACD player running through Marantz 7300 receiver with Energy C series speakers all around. Disc was Hotel California. Why on earth anyone would want to hear guitars work coming from behind them and drums in front is totally bizzarre.

The salesman gives the usual pitch that well that's the way the Eagles want you to hear it. Maybe the Eagles should retire if that's the case. Utter crap for a lot of money. Salesman fiddled with the amp brought it back to the front - nevertheless it was no great shakes.

There is expensive 2 channel and people do in fact spend on a lot on turntables. That is more to get every drop out of that medium. Why it can't be done for 2k I don't know, but diminishing returns is present. Throwing more money at something doesn't mean you get better. I'll gamble that a 15k Honda civic will outlast the top of the line Cadillac at over $60K Thus providing me the better service of what a car is designed to do - get a person from A to B reliably.

What this particular store SHOULD be doing is showing off new releases that were recorded in surround sound not trying to convert 70s music into that atrocious disc I was listening to today. Lifeless heartless sound that almost seems geared to the video game crowd.

[Woochifer]

If SACD is typical(and I know it's not) like what I just heard today and what most average people hear then they may as well give up now and forget the whole thing. I have heard better but this rather big chain in Canada had the Denon 2200 DVD/SACD player running through Marantz 7300 receiver with Energy C series speakers all around. Disc was Hotel California. Why on earth anyone would want to hear guitars work coming from behind them and drums in front is totally bizzarre.

...

What this particular store SHOULD be doing is showing off new releases that were recorded in surround sound not trying to convert 70s music into that atrocious disc I was listening to today. Lifeless heartless sound that almost seems geared to the video game crowd.

Actually, the problem is that the choice of material for the DVD-A and SACD remixes is typically NOT geared to the video game crowd, but rather aging baby boomers. I would love to see more new releases done up in multichannel, but SACD is the only format that can be released simultaneously for CD and multichannel mixes (essential for any kind of significant penetration into retail stores), and hybrid disc manufacturing capacity is totally booked right now doing reissues, so hybrid new releases are not feasible yet (the current issue of The Absolute Sound has a status report on SACD and DVD-A).

You're not the first one to complain about the Hotel California remix. There are bad surround music examples out there, just as there were a lot of bad stereo mixes in the beginning. Rather than generalize based on this one example, you should look for some of the better mixes done by the likes of Chesky, DMP, or Telarc, if all you want is something that sounds like a live performance. Chesky in particular has done some stunningly good work that virtually puts you into the same room with the musicians. Their two-channel mixes are also superb, but don't even come close to the depth and immersive effect that their surround mixes give you. Hotel California is a studio album, not necessarily intended to replicate a live performance.

Judging from some of the remixes that I've heard, a lot of older material is not necessarily a good candidate for surround remixing. The tracks needed to create a convincing envelopment and immersion effect simply might not exist. For example, the surround mix of Steely Dan's 1980 album "Gaucho" is awful. All of the instruments and vocals got discretely assigned to a particular channel, and it all sounds like five separate boxes with not a lot of good imaging qualities or spatial cues. On the other hand, their more recent "Everything Must Go" DVD-A is startling in how seamlessly all of the sound elements work together (both mixes were done by Eliot Scheiner, but Gaucho was the first one that he ever did six years ago, so obviously the state of the art has advanced considerably in the meantime; well, I believe he also did Hotel California, so that might reflect limitations in what he had available more than anything).

But, because a surround remix goes into the original multitracked master, it opens up all sorts of new possibilities to improve the basic audio quality, since as Terrence pointed out, two-channel mixes originally intended for vinyl required compression and all sorts of other tricks of the trade to get them to sound right in that medium. In a direct comparison, even the poor surround mix on Gaucho still yielded a noticeable improvement in the audio quality.

The other aspect of SACD and DVD-A that you didn't address is the remastering of the original two-channel source into high resolution, since EVERY SACD and DVD-A includes a high res two-channel mix. Even if you just have a two-channel system, the opportunity to remaster poorly done CD transfers is a welcome opportunity to correct past mistakes. I think a more valid way to assess the worth of SACD or DVD-A would be to compare the two-channel CD version with the two-channel high resolution track.

There is expensive 2 channel and people do in fact spend on a lot on turntables. That is more to get every drop out of that medium. Why it can't be done for 2k I don't know, but diminishing returns is present. Throwing more money at something doesn't mean you get better. I'll gamble that a 15k Honda civic will outlast the top of the line Cadillac at over $60K Thus providing me the better service of what a car is designed to do - get a person from A to B reliably.

Not another car analogy! The diminishing returns do exist, but the one thing about turntables is that approaches get more and more esoteric as you go further up the line, and the resulting components are not necessarily better sounding or even better built than the lower priced alternatives. The thing about that Civic versus Cadillac comparison is that the Caddy will haul more stuff, move faster, possibly handle better, provide more features, and have a quieter ride for that extra money. Whether or not one outlasts the other is irrelevant in a discussion of diminishing returns. It's an apples to oranges comparison since the performance aspects and physical dimensions are significantly different, and the top of the line Cadillacs have several performance advantages over the Civic, even if the Civic is more reliable in the long-run. But, an esoteric five figure priced turntable might not give you even a minor performance improvement over a more basic VPI or Well Tempered turntable.

[RGA]

Woochifer(Why are you not called Woofer?)

I was not attacking SACD though it sounded that way. No, I was attacking the store trying to sell people a new format and then to put on that Eagles disc is mind boggling. It is a bigger box chain though but still. Instead of having to hard sell people by giving them sales propaganda would it not be much easier to select some competant discs and let it sell itself?

If I'm running the store I'd be looking at discs from makers such as Chesky, Telarc, RR, Opus 3 etc. I realize 98% of buyers want top 40 and rock and roll but man there must be something better than that disc to choose. I have heard better systems, but many people hearing that may get turned off, certainly when you want over a grand for the player, and have to buy a bunch of speakers to impede one's living room to get sound that is pretty close to the already bad cd version.

Instead of reviving 70s music they should be trying to appeal to the 20 somethings or even teens who spend mom and dad's money. They're the one's filling the theaters to watch the ghastly movies being made and they're the ones ready to buy into anything with a COOL factor. Dare I say it but get Britney or Cold Play, or 50cent or some such music on SACD. Of course then I won't be going anywhere near it because the selection would make me nautious but hey I'm probably not their market. That's not really true everyone can be the market...but 70's music is probably not the best.

Well it is certainly true that the car analogy is not the best, The Civic is cheaper to run, easier to park, easier to load(I'm thinking the hatchback models where you can put a 32 inch tv in the back where you can't in the Caddy due to the shape of the trunk), far better gas mileage, will maneuvre better(depends on your meaning of handling but at low speeds I should think the Civic is better for quick turns in and out of areas. Overall speed and Luxury accomodations goes to the Caddilac - assuming they actually work. It's a good analogy depending how you view it, a bad one if you view it another way. If you perceive the extra $50,000.00 to get you from A to B over a 10 to 15 year span to better spent on a Caddilac then that is of course one's choice.

The extra money on a turntable. Well I've never heard an esoteric turntable. The TT1 from Audio Note is the best turntable I've ever heard, and it's less money than some of the highly touted Linn's. I'm not sure about it's build quality, has a wierd floating chassis...but then judging it agains my table I'll trade - so maybe floating tables are good.

I have gotten lazy and generally prefer cds for their ease of use. With a chanfger I can sit in my chair for 6 hours and listen to anything in my collections without getting up. Lazy you bet but it's nice. Getting up to hear one song on an LP or every 20-25minutes to change records? Convenience vs sound. And good cds are just as good if not better than LP. It depends on the RECORDINGS not the medium.

One reason I support SACD is not the format but the recording. If they take a horrible recording and make it good...then that is reason enough to go SACD - the multi-channel is icing on the cake.

[RGA]

Also
Woochifer


Sony got rid of that damn cheap DVD/SACD player in Canada anyway. Hi-fitommy lucked out. It was going for $229.00 but they dumped it and the replacements at more money don't have SACD.

The cheapest SACD player here now is a 400 disc DVD/CD/SACD player at $799.00CDN. Which actually isn't that bad a deal considering it does everything and even more and I have been impressed with the the CDP 355 300 disc changer. It's actually quieter than a lot of carousel units. It's strange that something so big can cost $280.00CDN and yet some dinky Sony digital Camera is even more money. Well it's not strange I know why but still.

[Woochifer]

I was not attacking SACD though it sounded that way. No, I was attacking the store trying to sell people a new format and then to put on that Eagles disc is mind boggling. It is a bigger box chain though but still. Instead of having to hard sell people by giving them sales propaganda would it not be much easier to select some competant discs and let it sell itself?

If I'm running the store I'd be looking at discs from makers such as Chesky, Telarc, RR, Opus 3 etc. I realize 98% of buyers want top 40 and rock and roll but man there must be something better than that disc to choose. I have heard better systems, but many people hearing that may get turned off, certainly when you want over a grand for the player, and have to buy a bunch of speakers to impede one's living room to get sound that is pretty close to the already bad cd version.

Instead of reviving 70s music they should be trying to appeal to the 20 somethings or even teens who spend mom and dad's money. They're the one's filling the theaters to watch the ghastly movies being made and they're the ones ready to buy into anything with a COOL factor. Dare I say it but get Britney or Cold Play, or 50cent or some such music on SACD. Of course then I won't be going anywhere near it because the selection would make me nautious but hey I'm probably not their market. That's not really true everyone can be the market...but 70's music is probably not the best.

Sorry, in rereading the thread, I realize that I missed that point. You're right in that the stores should be demoing more of the mixes that were originally done with 5.1 in mind, rather than 70s recordings that got repurposed for surround. But, it could just reflect the taste of the people running the store more than anything.

The first batch of DVD-A and SACD releases included an awful lot of the exact same titles that were in the first group of CD releases (e.g. Billy Joel "The Stranger" Mike Oldfeld "Tubular Bells" Fleetwood Mac "Rumors"). I would think that pop music has evolved a little bit since 1982. It's only more recently that more current titles have gotten into the pipeline. Considering that the so-called "Gen-Y" consumers are the ones who do more MP3 downloading, I would've thought that the record companies would target them with all sorts of incentives to migrate them over to the copy protected DVD-A and SACD formats. In quite a few cases, the surround version opens a whole new world of sounds compared to the two-channel version.

The extra money on a turntable. Well I've never heard an esoteric turntable. The TT1 from Audio Note is the best turntable I've ever heard, and it's less money than some of the highly touted Linn's. I'm not sure about it's build quality, has a wierd floating chassis...but then judging it agains my table I'll trade - so maybe floating tables are good.

The isolation system on a turntable is very important, and potentially expensive. Unlike with solid state components or digital sources, the overall audio performance of a turntable depends a lot on the ability of the unit to minimize external intrusions. The spring suspended chassis is one of the more popular isolation designs out there. AR introduced it in the early 50s, and it's very effective. The Well Tempered decks use an ingenious fluid suspension system to dampen any vibrations from reaching the tone arm, and it's also very effective. A lot of the obsession with isolation designs that went into turntables got carried over into all sorts of products designed for amps, CD players, etc. but with those types of components I'm not convinced at all that they are necessary or particularly effective.

One thing to keep in mind when comparing turntables is that the cartridge is at least as important (but much more frequently overlooked), as is the setup (the VTA, overhang, tonearm balancing, etc. all need to be accounted for).

I have gotten lazy and generally prefer cds for their ease of use. With a chanfger I can sit in my chair for 6 hours and listen to anything in my collections without getting up. Lazy you bet but it's nice. Getting up to hear one song on an LP or every 20-25minutes to change records? Convenience vs sound. And good cds are just as good if not better than LP. It depends on the RECORDINGS not the medium.

One reason I support SACD is not the format but the recording. If they take a horrible recording and make it good...then that is reason enough to go SACD - the multi-channel is icing on the cake.

In some ways, the whole ritual involved with LP playback makes music not so much a matter of convenience and background, but more of an event and something that commands full attention.

You do find good and bad examples in any medium, and really the thing to watch out for is the quality of the transfer, not necessarily the original recording since we have no way of assessing that unless we have access to the original master tapes. The great thing about SACD and DVD-A is that they necessitate going all the way back to the multitrack masters. In the process of assembling the multichannel mixes, the flaws with the two-channel transfers are exposed, and in some cases a new two-channel master gets created. Or at the very least, the two-channel transfer can be tweaked so that it sounds the way that should for a high res digital format. In addition, having five channels available eliminates a lot of the congestion with multitracked two-channel recordings. Even a clean two-channel recording like Pat Metheny's "Imaginary Day" sounds much more open and natural in 5.1, and we're not even talking about the spatial cues which sound much more targeted and deliberate.

[jbangelfish]

And a lot of good points have been raised. I do believe that the technology is present to make music in the home better than ever. I don't know how much better it can be than 70's or 80's technology but there is always room for improvement, no matter how minute. It is even possible that good receivers are being made today, this just did not used to be the case, when compared to separates. I have not owned a receiver since 1975 so things could have improved since then. The fact that a 5 channel system gives each speaker section a smaller job could make a system more efficient with less power to each. A typical larger 5.1 receiver seems to be in the 100wpc area. I am more accostomed to having two channels with 200 to as much as 1000wpc which does liven up a pair of speakers.
I agree that some people will buy anything, no matter what the price just to say that they have it. I also think that these horribly expensive components probably sound as good as money can buy. For most of us, we can get excellent results by spending a lot less.
Someone mentioned the new vs old with 901's and AR9's and this is certainly true. When Bose ported the 901, they ruined it. I believe they did this in an attempt to make them more efficient. They also switched from butyl to foam surround which was easier to push with less power. Original 901's, series I and II were notoriously power hungry. I have not heard new AR9's but anyone with the old ones will tell you that they'll keep what they have.
As to the LP vs CD debate, I still haven't heard enough great CD's to prefer them over LP. I know that it is possible to make excellent CD's and I have said before, possibly even better than LP. The fact remains that I own a lot more great LP's than I do CD's. I do have 20 to 1 LP over CD which is at least part of the reason. When I hear a great CD, I'm just as happy to enjoy it as an LP.

[Woochifer]

If you made any attempt to master vinyl records with the dynamic range found on today's recording, the needle would jump off the record and kill you!!

So, THAT'S what happened when I stuck that direct disc on the turntable all those eons ago. All this time, I thought some serial killer with bad aim was lurking abouts.

I didn't think that anyone would buy an air conditioned dog house advertised in the Sharper Image several years ago, but people did.

T-man, you're coming at it from the wrong set of priorities dude! Our house IS the dog's house, and any kind of air conditioning is for the dog to decide, and our privilege to enjoy.

I was floored when I found out that men PAY for sex, but they do.

Ah! So, that's what I was doing wrong all those years! Nookie to fund liquidity ratio is a direct rather than an inverse relationship. That damn stats prof, he was just pulling a fast one on all of us starving students. Now I'll need to change all my socioeconomic assumptions and change my political affiliation.