DSD vs. PCM digtal, a few thoughts.

Yashu

Troy, I hate to say this, but I am going to have to agree with what you have said earlier regarding DSD as a digital format.

I have researched the technology and I see that it is superior to PCM when given the same data size. I understand why SACD, disregarding how Sony has basically doomed the format by keeping it closed, as a digital format using DSD, would be a definite improvement over standard redbook PCM, or even PCM at 24/96.

Technically, either format can reach the same limits, but it seems that DSD is more efficient, as it needs less space to do so. DSD audio recorded onto a CD as media, would be superior to PCM. It would take many times more data to hold a PCM encoded RAW .wav to match the same dynamic range.

There is one thing, however, in favor of PCM... this is regarding the processing and recording of PCM data... using noise shaping, one can essentially push the dynamic range of a 16bit PCM disc to close to 20bit or more, however, this involves modification of the sound, the music itself. There are arguments that the human ear wouldn't notice, because it pushes this noise outside the general understood range of hearing, however, as we all know, everything matters.

If Sony would have played their cards right, they could have taken this superior format and opened up the ability of anyone to record or press in DSD, and I think that if they did that, SACD would have taken off in the same way that DVD took off and ended the use of VHS for almost every application. Sony has not done this. They have kept the ability to use the format tightly controlled, and so limited the adoption of DSD as a standard.

I think, Troy, that you are right, DSD is a very good audio format, using 1bit, and sometimes several 1bit DACs to recreate a better, more natural analog signal that easily surpasses the 22.5khz limit of the redbook CD. After doing my research, I am almost angry at the industry for not allowing the wide adoption of DSD, because I think the only thing holding it back is the extreme limitations that Sony has put onto the format - SACD.

I doubt that the difference between PCM and DSD would be as dramatic with 24/96 PCM, but that takes several GB, where DSD can get the same dynamic range out of the space on a standard CD. Knowing this, it is clear that Sony has shot themselves in the foot, or they just don't want the world, or more importantly to them, RIAA labels, to mass release in a format that matches the original master recordings. Either way, we, the music listeners, music lovers, are the ones left to suffer, as artists continue to use PCM because it is an open format with no restrictions, therefore anyone can use it.

We disagree on the *why* or *ifs* about SACD, but I couldn't go on without saying that I, at least agree, that DSD is a very good format, and I wish that it was widely adopted and easy for any artist to use, and easy for any artist to get pressed.

I think that the future is still bright for DSD, as Sony will not tightly restrict it's use forever. Eventually Sony will either give up their battle against consumers and just allow DSD and SACD to be used and made by everyone in an open fashion, once it becomes something that Sony no longer makes money on, but how long that will take is beyond my guess.

The blu-ray/HD-DVD format war can give some insight to what may happen, and it doesn't look good (look into Sony's war wounds and implications to other studios). SACD may very well fail as a next gen audio distribution media, but DSD encoding is certainly the future.

Danny Tse

Yashu,

Have you listened to a DSD-remastered CD? In my experience, DSD almost always makes a positive impact on the sound quality....even when the music is released on regular CD.

heiney9

DSD isn't the end all be all. A great DSD is better than a good PCM. A great PCM is better than a good DSD. As always there are exceptions.

A couple of technical papers for those so inclined.

http://sjeng.org/ftp/SACD.pdf

against DSD and pointing out it's flaws.

http://www.extra.research.philips.com/mscs/publications2002/dsd-aesformat.pdf

for DSD pointing out some things possibly overlooked in the first paper.

Have fun

H9

Yashu

DSD isn't the end all be all. A great DSD is better than a good PCM. A great PCM is better than a good DSD. As always there are exceptions.

I think we have done some of the same research Heiney. The thread about SACD really got me going and wondering what the hubub was about and why artists haven't embraced an open format, PCM on DVD, over SACD, closed format DSD. I found that DSD has advantages, but that we have a lot more experience with PCM, and we have ways of creating very good PCM mixes. I would like to see DSD mature into a consumer format that is open to everyone, like PCM is... DSD would mature, and we would see what it is truly capable of.

DSD was the basis of laserdisc, and in terms of video/sound quality, it was better than DVD, when done right. I know that it is capable of great sound, but right now it is locked up, and so 99% of artists either don't have access, or don't release on SACD because of the limited market. I like the way it generates an analog signal though... it is very elegant, and almost beautiful. I wish I could play with it myself, but in the end, it all becomes s/pdif to my DAC anyway... I am not going to buy an SACD player until I can make an SACD, or anyone else for that matter. SACD is useless to me if none of the musicians I listen to have access to the format.

Danny, give me an example of a good DSD mastered CD. I would like to have a listen.

heiney9

DSD as appiled for SACD is where it's at rather than 1 bit Delta Sigma Dac's in std. redbook applications.

I have a 1 bit Delta Sigma dac and an 18 bit PCM Dac and there is no comparison. The PCM version with top quality Burr Brown chipsets are far superior to the 1 bit system. Of course this isn't in an SACD application.

H9

EDIT:
I believe 1 bit processing uses PWM (Pulse Width Modulation principles) and PCM is of course (Pulse Code Modulation). PWM has some real issues that need to be overcome compared to PCM.

Yashu

PWM has some real issues that need to be overcome compared to PCM.

Yes, I have heard that noise is a big problem. I have basically read that the noise floor is much lower on PCM.

I know I love my NOS DAC even at just 16bit it sounds so liquid. I don't have a DAC for DSD, nor an SACD player, so I can't directly test, but I have listened to SACDs and did not hear anything that made it *better* than PCM at 24/96. It did sound good though. I really wish more artists would take a stand and move in the direction of high resolution, whether it be DSD or PCM. It has to be open, it must be something that anyone can create and playback, independant of the corporate interest.

I think PCM sounds as good as it does is because we have had more than 20 years to perfect it. DSD would advance in a similar fashion (and it has, multiple 1bit feedback to reduce the noise). Either way, Sony had their chance and I think they lost it... I don't see SACD as the next gen format, but I do see promise in DSD, even if for the fact that PCM has been pushed to the limit already... the thing is, do we really need DSD? With media size expanding like it is, high resolution PCM can be easily accommodated. Past 24/96, hell, half the speakers in the world have tweeters that break up around 48khz or even lower.

Danny Tse

Yashu wrote: »

Danny, give me an example of a good DSD mastered CD. I would like to have a listen.

Rolling Stones, Elvis, Brian Eno, Sam Cooke, Bob Dylan, etc. While the Rolling Stones and Bob Dylan titles were originally issued on SACD, they have subsequently been re-issued on regular CD. The Elvis and Brian Eno titles were remastered with DSD and were never released on SACD. You can also try CDs from labels like Telarc.

Yashu, I think there are a couple of big hurdles SACD have to overcome....the willingness of the record companies to release SACD and the attractiveness of buying music online. I don't think I need to go into details with either issue.

The technology is available to almost anyone. If you look, there are plenty of indie artists that have released SACD. So it's really down to whether an artist want his/her music to be heard in this particular medium. If you're talking about grassroot-type home studios, yes the choices of recording decks is limited. I believe Tascam and Korg make DSD recorders for home studios. However, if you want SACD to be pressed, you will need to bring your master to a SACD pressing plant.

Yashu

However, if you want SACD to be pressed, you will need to bring your master to a SACD pressing plant.

This is the reason why it will never take off. Until anyone can burn one on the PC, we will be using PCM 'till the cows come home, or at least, like your examples, PCM will be the final product. I can see production work growing in DSD. I have done some production work myself, and while I have no huge complaints about PCM, it would be cool to try new things. Problem is, I can't make an SACD, unless Sony lets me... fat chance. I can make a CD, I can make a DVD, I can get vinyl pressed, but I will probably die before SACD burning/pressing is offered by smaller independent (from Sony) facilities.

I should look into the Dylan and Eno stuff... I can't remember the name of this one Eno album, but it would be cool to hear it against both the old CD, the remastered CD, and the MP3s I have somewhere.

hearingimpared

The new Rolling Stones rerelease of "let it bleed" on vinly is DSD!

Systems

heiney9 wrote: »

DSD as appiled for SACD is where it's at rather than 1 bit Delta Sigma Dac's in std. redbook applications.

DSD Direct Stream Digital used for SACD is a 1bit processs.

I have a 1 bit Delta Sigma dac and an 18 bit PCM Dac and there is no comparison. The PCM version with top quality Burr Brown chipsets are far superior to the 1 bit system.

While BB make some excellent sounding multi bit DAC's,the better 1bit Delta Sigma designs from Cirrus Logic like the 4328,4329,4390 were used in some stellar sounding products from the likes of Audio Research,Meridian and Lexicon.The choice of the chip is only part of the equation how it is implemented is very important.The analog stage following the DAC and power supply etc all play a part.

TroyD

The reason that SACD didn't achieve widespread acceptance has almost nothing to do with anything technical.

And, thank you, it is superior to PCM

BDT