DualDisc may not be "all that" according to this (1 Viewer)

[LanceJ]

O.K. guys what official governing body has stated with what sampling rate/word length "true" hi-res actually begins?

As I and others have mentioned before, the word length has a LOT to do with how accurately the analog waveform is constructed i.e. 24 bits gives the DAC many more voltage choices with which to build that sinewave. And IIRC, much less dithering (digital "noise") is required to be added to a XkHz/24bit signal for the final version us customers hear, compared to a 16bit signal (dither can audibly alter the sound of the music).

As far as higher frequencies affecting the ones under 20kHz and adding realism to the listening experience, well, as far as solid scientific evidence goes the jury is still out on that one. But this is what the real world has to say about 20kHz+ frequencies: most analog tape and associated tape recorders don't reach that far up anyway, and the same goes for most studio microphones (though this may be slowly changing because of the hi-res formats). And lots of speakers' response past 20kHz, especially those with metal dome tweeters, either drops off quickly or become quite ragged in turn rendering the signal sent to them nearly useless.

And from what I've seen myself and read about, Sony is the label putting out the huge majority of those DualDiscs with 48kHz/16bit stereo tracks :rolleyes, and according to numerous online reviews, not to mention all those fake-y 5.1 surround mixes that supposedly sound like the "hall" button on a $150 receiver.

 

[Kevin C Brown]

Lance- AFAIK, word length only has to do with dynamic range. Sampling freq is what gives you more samples to better represent a sine wave. Sampling freq is across time, word length is a static snapshop in time.

??

Plus, an extended freq response allows you to use a shallower antialiasing filter which results in less ringing and digital artifacts.

 

[Marc Colella]

Yep, it's not a format issue - it's a label issue.

And as usual, Sony seems to be the culprit. Just look what they're doing to DVD releases now.

In any case, regardless of who wins the HD format wars - it will have no impact on audio. The labels know that people just don't care about Hi-Rez audio for music. I think the best we can hope for is nice audio from concert videos and such... but nothing that's audio-only.

 

[Michael Harris]

I just bought my first, and last, DualDisc. Yesterday I purchased two copies of Bruce Springsteen's "Seeger Sessions". One for me and one for my mother as a Mother's Day gift. I put mine in my Sony ES series CD player, saw the TOC being read, and nothing. Then I noticed on the rear of the cover that the CD does "not conform to CD specifications". Wow, A Sony CD that does not play on a Sony CD player. I put the CD in my Sony DVD player and no problem. I tried the DVD side and at first my player would not recognize the disc but after some loading and reloading, success.

Ok, I like using my CD player for playing CDs. What do I do? I made copy of it on my computer and the copy plays perfectly on my CD player. I figured I'd better provide my mother a copy of it too in case the original doesn't play in her Sony CD player.

Next time, I'll read the fine print. If it doesn't have the CD logo on it, I just won't buy it.

 

[LanceJ]

True......but according to this discussion about how PCM is handled in newer DACs I'm not sure anymore how important this issue is. According to what engineers in that thread are saying particularly posts by "Tweaker"* and "Black Elk", nowadays** most PCM is upconverted to frequencies in the mHz range and filtering is then much less of an issue (see page #5 in that thread). But there's more to it than that so to get the full story one really needs to start at the beginning of that thread, and as a side-effect you'll see that DSD and present-day PCM are rather close cousins.

* Tweaker is a very well-known mastering engineer.........

** actually, for more than a decade now; but supposedly those first 1-bit convertors in the early 90s were supposedly not all that great (my Technics SL-PG4 with its "MASH" convertor bought in 1991 sounded O.K. to me, but then again, I never directly compared it to my newer Technics and Pioneer players either [both are 2003 models]).

 

[Kevin C Brown]

From the SH link:


A sine wave is a construct in time. Sampling freq is across time. (Horizontally modelling the sine wave.) The word length comprises the signal at one instant in time: there is no sine wave in that case. It is simply one "step" in the sine wave. (Vertically modelling the height of the sine wave at one instance in time.)

16 bit word = 65,536 individual voltage levels
20 bit performance = 1,048,576 levels

I'd be curious if there's ever been a double A/B/X blind test to see if the human ear can actually tell the difference between these two.

I still hold that word length is not as important, mostly because of how current CDs are mastered where only a small part of the actual dynamic range of even 16/44 is used.

 

[LanceJ]

If that one point in time is not the CORRECT point, it definitely can have an effect on the audible signal. Using a 0 to 5 volt scale, what if the ADC connected to the microphone gave one of those points in time a 1.7V value but the 16bit DAC in your player could only come up with 1.5V value? I'm using overly chunky numbers to make a point, but that's basically what is happening with a 24bit vs. 16bit DAC.

As far as the ambience retrieval/dynamic range issue, many people with better-than-average systems have noticed that at low volume levels, acoustic music and especially complicated musical passages (like massed strings and choirs) on a CD can become rather indistinct i.e. the various instruments and voices are all lumped together. That makes sense because only the first few bits of the sample word are being used, resulting in really chunky - and imprecise - voltage levels being generated.

But to clarify where *I* stand on this issue: I don't listen to classical or choral music and I only listen to a smattering of jazz. So for me this 16 vs. 24bit issue is almost an academic argument.

But......when I bought Eric Johnson's Ah Via Musicom dvd-audio & played its 96/24 LPCM 2.0 track on my $180 Panasonic dvd player, with only a small amount of concentration I did hear what all those articles and reviewers are discussing NOW. But this was in 2002 and at that time I really wasn't sure what I was supposed to be hearing (this was before I learned about the advantages of 16+ bits) so I just sat and let the music play, but within just a couple minutes, on quieter passages & without straining to hear them on my $900 Technics receiver/Boston Acoustics system, I noticed that reverb tails on plucked guitar strings, drums, etc lasted much longer than on my CD. I've owned that CD for a decade and listened to it dozens of times so am very familiar with it. Also, the 96/24 track did not sound at all like it was remastered - unfortunately, it had the same unpleasant harsh/grainy sound and too-hot treble.*

And as was already written, sine waves are easy for a DAC to build, so having extra sample points to make "better" ones doesn't really help that much. And those details so often brought up that are in between the sample points of a 44.1/48 system couldn't be heard anyway, because that would mean they are located past the accepted upper limit of 20kHz for human hearing.

Most of the advantages of 96kHz/192kHz/DSD always seem to end up being connected to their filtering habits, so I wish someone would do a test with those formats but use a brickwall filter with them set at 20kHz to see once and for all if all those extra samples are actually making a difference compared to the 44,100 samples of the CD format.

* I'm one of the people that returned the disc as soon as I read about Eric's apology for it >>> to read the entire sad story of this incredibly botched disc i.e. the surround mix, go here. It was so badly done by Capitol - and done without Eric Johnson's knowledge - Eric himself publicly apologized for it and got Capitol to stop selling it. According to Eric himself (about six months ago) he is supposed to be remixing the album himself so I'm really looking forward to this in whatever format it's in.

 

[ElevSkyMovie]

I have this dvd-audio disc as well. Unfortunately, the stereo track is 16/48. Hard to believe, huh? Why bother. The 5.1 is 24/96, but it was remixed without Eric or his knowledge. As you have noted, it was not mixed correctly. It's basically a worthless disc, unless you enjoy the 1 and only music video on it.

I also have Queensryche's "Empire", also an EMI disc. The stereo tracks on it are also at 16/48.

 

[LanceJ]

Nope, it was a 96/24 linear PCM track. And I clearly remember the player's onscreen info display saying so. Highfidelityreview.com's review states the same thing. It was one of the first dvd-audios to have such a track.

My 5 year old receiver can't handle a 96/24PCM data stream so I used the dvd-video player's analog outputs.

Maybe your particular player is keeping its digital output activated, but is downsampling the data stream to your receiver to prevent access to the full hi-res signal? My own Pioneer DV-656 dvd-audio player does this with most discs (onscreen display says "Digital Out Converted", even though the downsampling option box is not checked in the player's audio options menu). 48kHz/16bit is supposed to be a common format for downrezzing.

Fun factoid: it was also the first time I saw evidence of copy protection on a dvd-audio: when playing that 96/24 track, my dvd-video player's optical digital output was totally shut off (I know because I looked).

 

[Paul.S]

Hmmm--Kyle is my Pio 563A just wrong when it reads '96/24' when playing back the Empire stereo tracks? Methinks there's something fakakta there though because it also says '96/24' for the m.c. . . .

Cheap gesture to getting this wayward thread back on topic: does anyone have the Doggystyle Dual? I have the The Chronic Dual and like it.

 

[ElevSkyMovie]

Yes, you guys are right. I had tried to extract the 24/96 audio before. The tools I was using said the stereo tracks were 16/48. It was able to extract the audio, so I thought it was correct. I looked again today and the audio is 24/96. It is in the VIDEO_TS folder, so any dvd player should be able to play the high res stereo tracks. the tracks are quite compressed. If I knew how to post a pic, I'd show you the cd/dvd-audio differences between "High Landrons" on "Ah Via Musicom". While on quieter passages I hear more of reverb tails, etc, I think I listen to the cd more since it's less compressed.

 

[Lee Scoggins]

"I consider those hi-rez, is that not correct?"

No, you need faster sampling rates in addition to word length for true hirez. Most engineers I work with consider 24/88.2 or higher PCM or DSD to be hirez.

Much ado about nothing is the impact of filtering effects on hirez PCM or DSD. These effects have become inaudible as ADC and DAC chips have improved and new implementations and use of dither have been utilized.

It's hard to describe the benefit of hirez until you hear a good comparison of a live event then listen to it captured (on even a great quality ADC) in 16/44 then 24/88.2. There's no question that the extra sampling rate improves the accuracy of the tonality of the music and the width and depth of soundstage. It's really quite remarkable.

 

[Lee Scoggins]

"I'd be curious if there's ever been a double A/B/X blind test to see if the human ear can actually tell the difference between these two. "

Actually there have been tests of the improvements in both word length and sampling rate. Some Japanese scientists have an AES paper of 24/96 and its positive impact on sound. Think about word length as the precision of the height of the rectangles under the wave and sampling rate as the number of rectangles under the wave per unit of time. Increase both and you get a sharper picture (and better sonics) of the wave. See Ken Pohlman's books on Digital Audio.

 

[ElevSkyMovie]

To me it's just common sense. If you've had calculus, you know that the more you slice the curve (audio signal) up, the more accurate representation you're going to have. Is there a limit at which there is no benefit? Yep. Have we hit that point yet? Maybe with dvd-audio or SACD, but not with cd.

 

[Paul.S]

I was talking about Empire.

 

[ElevSkyMovie]

I understand. We were talking about Ah Via Musicom. Empire was made at the same time Ah Via Musicom was and has the same specs. I'm sure it also has a 24/96 stereo track. It is part of the dvd-video section (since its LPCM and not MLP).

 

[LanceJ]

Common sense doesn't always help explain certain physical and mathematical concepts.

I'm not trying to use this argument as a way to make your opinion irrelevant, but common sense also tells you that when you look down a set of railroad tracks, the two rails "definitely" meet at some point several hundred feet away......which is completely false.

And if a DAC can't produce an accurate sine wave with points taken from a 44.1kHz data stream, why would it be any more accurate with points taken from a 96/192/DSD data stream? In fact those smaller/more delicate slices would need a better DAC to produce them properly.........

....which is the point I was trying to make in this and other threads: if a DAC is made carefully enough, 44,100 samples theoretically *is* enough to create extremely accurate music sinewaves. And I've read enough reviews of DACs like this to know they exist. BTW: The sample word & filtering issues are separate issues.

Sine waves are just not that difficult to create.

As a hobbyist, I don't really want to speculate further until I see the results of a properly done professional test, but many pros with high quality* 44.1/48 24bit DACs say they can't tell the difference between those and a 96/192 24bit DAC (I am just repeating what they said - I have not heard this gear myself).

* and I do mean high quality i.e. standalone DACs costing in the $2500+ range.

 

[Lee Scoggins]

"And if a DAC can't produce an accurate sine wave with points taken from a 44.1kHz data stream, why would it be any more accurate with points taken from a 96/192/DSD data stream?"

Most hirez DACs perform better at recreating the analog waveform. And because they have more musical information, they add resolution over 16/44.1. Lots more resolution.

 

[LanceJ]

Warner: DVD Albums To Replace DualDiscs

a couple excerpts from this Twice.com article:


So then it will be......drum roll......a dvd-audio disc!!

I think this may a stealth form of reintroducing hi-res audio - NOT the dvd-audio format - to the marketplace. The hi-res tracks will be just another potential feature to be looked for when scanning a dvd album's label.

 

[Chris Gerhard]

So just like DualDisc, the DVD Album can include DVD-Audio. I hope this time, you can tell what is on disc. With DualDisc it is sometimes difficult from the case. It doesn't look like anything the consumer will want once again unless having AAC or MP3 transferrable to a PC or iPod or MP3 player in addition to high quality audio for the home DVD player does that. I don't have any discs or music on PC in either format so I don't have a feel if that has any value but I do know that people listen to AAC, iPod and MP3 and for the most part don't know what DVD-Audio is.

Chris