Why I prefer DSD format

[jelanier]

No matter which format you prefer, you are always stuck with the manufacturers d/a converter and/or analog amplifiers. I am a bit of a vacuum tube buff and it pains me to thing of a cheap op amp as a preamp/buffer inline which is so common in CD/SACD players. Sure, you can spend thousands on an SACD player to get better analog circuitry, but this is not needed.
The truth is that DSD is in many ways is like an analog format. It does not require digital d/a conversion. A simple passive filter is all that is required to decode DSD to analog.After passing through the passive filter, the signal enters amplification/buffering of your choice! Wouldn't that be nice?

Now all we need is for the manufacturers to give us discreet DSD output ports. Even if the format were 24 bit 192khz, converting to DSD for a discreet output port is still an advantage because the decoding option is ours if we want it! This would still avoid the damage done in the analog domain. We need some DSD PC audio cards as well

 

[avliner]

Jelanier,

welcome to the forum!

Matter of fact, we do have a quite affordable player now ( $ 160) that do deliver DSD signal; i.e. OPPO 980HD, so as you said, you don't need anymore to spend thousands on a real SACD player though.

Regards, Chuck

 

[jelanier]

Yes, I am aware of the Oppo with HDMI v1.2. The problem is, it is over HDMI, meaning that it is copyright protected...ie not active all the time. I had plans to call them and get the scoop.

 

[avliner]

Not 100% sure, but I think it does deliver a true DSD signal over HDMI.

OTOH, I've been reading over at AVS that Sony has a new FW that even delivers DSD over optical/coaxial cables for the PS3.
It seems to be only a matter of copy protenction though; anyway I'd appreciate to have your feedback once you got a reply from Oppo.

 

[jelanier]

Bad news. The Oppo does not transmit DSD streams over the HDMI port. The DSD is embedded in video and must be stripped by the receiver and re-clocked out.

Also on another sour note, the unit does not do true DSD processing for it's normal analog outputs. It converts to pcm...then, d/a then buffer ...UGLY!

 

[wanjeyin]

Also on another sour note, the unit does not do true DSD processing for it's normal analog outputs. It converts to pcm...then, d/a then buffer ...UGLY!

Do you know this for certain? Where were you able to find this out? I have a 980HD and was also wondering how the inner workings of the 980HD works with respect to DSD/SACD processing.

AJW

 

[jelanier]

For certain? They will not send me a service manual so I can't check it out for myself. They say they do not have them. But, I called them and they told me the bad news about the processing.

Here is a quote:

The DV-980H handles DSD audio with its main decoder chip made by Mediatek. For analog output, DSD is converted to PCM at 88.2kHz/24bit before D/A conversion. For DSD over HDMI output, DSD is not processed. It is packetized according to the HDMI 1.2 specification and the receiver restores the DSD stream from the audio packets. Due to the packetizing procedure there is no separate DSD streams over HDMI. The HDMI receiver may construct separated DSD streams though.


Best Regards,

Customer Service
OPPO Digital, Inc.
2629B Terminal Blvd.
Mountain View, CA 94043
Service@oppodigital.com
Tel: 650-961-1118
Fax: 650-961-1119

 

[avliner]

Well,

perhaps no DSD thru HDMI, as stated by Oppo, but what about true DSD over multi-channel analogs?? It seems to be the last hope though

 

[jliedeka]

Well,

perhaps no DSD thru HDMI, as stated by Oppo, but what about true DSD over multi-channel analogs?? It seems to be the last hope though

Analog is analog. The Oppo D/A converts DSD for the analog outputs. I use the analog outs from my 981 and it sounds pretty good. I had no choice there, I have an older receiver.

Jim

 

[jelanier]

Oppo DSD Process

Perhaps you didn't understand my post. The Oppo does NOT have true DSD processing for it's analog outputs. It converts the DSD to PCM first, then decodes with a PCM d/a. True DSD processing is a completely different animal.

 

[fmw]

Based on the follow excerpt from the Wikipedia DSD entry, I would conclude it is all much ado about nothing - or at least nothing meaningful. It appears the experts can't agree.

"There has been much controversy between proponents of DSD and PCM over which encoding system is superior. Professors Stanley Lipshitz and John Vanderkooy from the University of Waterloo, in Audio Engineering Society Convention Paper 5395 (2001), stated that 1-bit converters (as employed by DSD) are unsuitable for high-end applications due to their high distortion. Even 8-bit, four-times-oversampled PCM with noise shaping, proper dithering and half data rate of DSD has better noise floor and frequency response. However, in 2002, Philips published a convention paper arguing against this in Convention Paper 5616. Lipshitz and Vanderkooy's paper has been criticized in detail by Professor James Angus at an Audio Engineering Society presentation Convention Paper 5619. Lipshitz and Vanderkooy responded in Convention Paper 5620."

 

[fmw]

The truth is that DSD is in many ways is like an analog format. It does not require digital d/a conversion. A simple passive filter is all that is required to decode DSD to analog.After passing through the passive filter, the signal enters amplification/buffering of your choice! Wouldn't that be nice?

I don't know why it would be nice. D/A and A/D conversion are very mature and perfected technologies that produce amazing accuracy and fidelity to the original signal. I wouldn't call DSD analog-like, by the way. The first D stands for digital.

 

[jelanier]

DSD "analog like"

First, you are comparing apples to oranges. In the Oppo, the DSD is Converted to 88khz PCM, then d/a. That is a format conversion. This is not as good as DSD or PCM!!

DSD IS analog like. DSD is a form of pulse width modulation. (I happen to design Pulse Width Modulators.) It is VERY analog like. The "symmetry" of the square wave changes depending on the analog voltage that it is reference to. No digital device is even needed to demodulate this signal. The same can't be said of PCM.

Some commercial "high end" SACD players incorporate 2nd order passive filtering to accomplish this and avoid the digital processing of the DSD signal.

In reference to DSD VS 192k 24b PCM..I think they are both great and have their advantages and disadvantages each. But, that its not the subject.