DSD vs PCM: can you hear the difference?

I've only compared SACDs played on my Oppo BDP-105, to 24/88 and 24/176 PCM conversions of the SACDs, played from my Mac mini (bit-perfect, integer mode, etc.) into my Oppo 105. Using that comparison, I prefer the SACD/DSD, but (A) it could just be something to do with the Mac mini playback chain, and (B) I prefer the SACDs, but I am not at all certain that I could reliably distinguish between the SACD and the PCM conversion in a truly blind ABX test.

As far as DACs go, don't most modern DACs - that is, delta-sigma DACs - effectively convert everything to DSD internally at some point? In other words, isn't a delta-sigma DAC 1-bit at heart? Or do I have this all wrong (which is entirely possible!).

 

Yes sigma delta is similar to DSD, but it is not strictly DSD. DSD is actually a subset of sigma-delta modulation.

Most sigma-delta DACs perform multi-bit sigma-delta conversions using somewhere between 2.5 and 4 bits internally. So these DACs are technically neither 100% pure DSD nor anywhere near pure multibit PCM DACs internally.

Regardless, DSD still sounds better when it enters a sigma-delta DAC as DSD than it does when it has been converted to PCM prior to entering the DAC.

 

Thanks for the clarification - much appreciated. And I definitely agree with your final statement.

 

I would bet that given identically spec'd equipment, in a blindfold test, nobody could accurately tell the difference.

 

Just curious. I don't know anything about it. Why is it more of a PITA for studios to use DSD?

 

Because DSD is difficult to work with. Common tools such as Pro Tools (and almost everything else out there) can't process it. To process it you largely need to either need to convert it to analog, and then re-digitize it, or you need to convert it to PCM. There are only a handful of tools out there which can work-with native DSD, and all of these are relatively limited in their capabilities.

By comparison, PCM is easy to work with. It can be processed in an almost infinite number of ways with thousands of different tools and never leave the digital domain.

So from the standpoint of any non-purist recording studio it is most definitely a PITA to deal with.

 

For what it's worth, Jason from Schiit Audio talked me out of buying their Loki because he said that DSD files converted to PCM through something like JRiver won't sound any different than native DSD. First time anyone from any company has convinced me not to buy their product. This was before I bought any product from them and I was so impressed with that type of communication I now own the Gumby and love it!

 

It's one of those things that sneaks up on you as you are listening. The music is playing then all of a sudden you notice a realism with the tone of the instruments and their placement.

 

I've done several recordings with a split mic feed, one to a Korg recording in DSD and one to a Sound Devices 744 recording PCM. I think DSD is closer to the live event.

But you can get great sound from either format.

 

It's not difficult at all to record in DSD. Modern workstations do everything you really need and Korg has made recording in it very accessible for small studios and bands on a budget.

Distribution is not harder than hirez pcm files since the files are similar size.

 

My Pioneer Elite A/V receiver accepts DSD over HDMI or USB but converts it to 176.4 Khz/24 bit, so I made this test: first rip all my SACDs to ISO (using a friend's PS3) extract the DSD files from them with a program called ISO2DSD and then convert the DSD files to 176.4 Khz/24 bit with Weiss Saracon. Saracon configuration is as follows: 176.4 Khz, 24 bit, +3.5dB, dither/noise shaping POWEr3. To my ears and using this configuration Saracon does a better job at converting DSD to PCM than my Pioneer Elite Receiver.

 

The conversion happens in the Blu-Ray player, or in software (if on a PC). The "de-embedders" I believe you speak of do not do any actual DSD to PCM conversion. They just grab the digital audio signal and pass to a more common digital interface (usually SPDIF, sometimes Coax). Some also have a small output stage for running analog out, useful if your DVD/BDP lacks analogs.

I'm using one now with my Sony BDP-370. I've toyed with the idea of grabbing an audiophile universal player, but using the Sony as transport and sending PCM to DAC seems far more reasonable an option. Especially since most of my listening is now PC to DAC. With the exception of some Blu-Ray audio disks and a small handful of SACDs.

TD

 

Only because your brain subscribes value to "pure DSD" even though it's already been converted to PCM in your player, and several more times in the production process in most cases.

DSD is not magic.

Meanwhile -- are their upgrades/mods available to the Oppo 103 that allow for full resolution from Coax/SPDIF? PCM converted, of course.

 

That is not my point. Yes it is easier to record in DSD now than it used to be. And please do not take my post as being a dig against DSD. I love DSD, and own nearly 800 SACDs which should attest to this fact. I'm just recognizing the unfortunate downside realities here from the recording industry's point of view.

The problem is that, so far as I know, the tools do not exist for natively mixing, mastering, applying EQ, reverb, etc inside of the DSD domain. You either have to convert to analog, and do all of that work in the analog domain, and then re-digitize, or you have to convert to PCM, run pro-tools (or similar packages), and then convert back to DSD.

One caveat here: It is possible that my information is out of date and that all of these tools now exist for natively processing DSD. But I doubt it very much due to the huge technical challenges in doing this.

But I will agree with you that if you are an audiophile label which never mixes or masters anything, then DSD is easy to record with now.

 

Most modern players do not convert DSD to PCM. That was true of the early generation universal players, but it is not true today since almost all modern sigma-delta DACs both natively understand and decode DSD now.

Yes there is. It's called the Vanity HD card. The regular version does convert to PCM as you desribe. But the DoP version of this card most definitely does not convert to PCM! It outputs genuine DSD via DoP over SP/DIF.

 

Thanks. What I'm looking for is a mod that:

a) converts DSD to full resolution 176.4 PCM (the oppo is restricted at 88.2, which they claim is by design)
and/or
b) sends full resolution LPCM from Blu-Rays and converted SACD straight to the digital outputs (not downsampled), negating need for hdmi de-embedder, etc.


Just found source for this mod. Wow - ask and ye shall receive, I think. Need to spend more time with the highly informative yet somewhat confusing site. Not clear the diffs among the mods.

But a player outputting full res from the digital outputs would be killer. So long as it's not down sampling as the player does currently with sacd and blu-Ray.

 

Denti, just throwing this out there for you to consider: NAD's M51 DAC w- HDMI.

NAD M51 Direct Digital D/A converter »

The NAD resamples everything you throw in its direction and converts it to a pulse-width-modulation (PWM) signal, the native format for DSD, at a sampling rate of 844kHz, all controlled by a clock running at 108MHz. It doesn't care if you want this done or not—it just does it. This is done within a 35-bit architecture using a similar PCM-to-PWM approach as the company's M2 integrated amplifier
...​

This time the M51's display read 88.2kHz—clearly, an SACD stream fed to the M51's HDMI input will be downsampled to PCM. NAD has confirmed that the M51 can't accept DSD audio via HDMI, but can accept SACD playback if converted by the BD/SACD player at up to 24/192 PCM.​

 

Some of you might find some of this interesting:-

DSD vs. PCM: Myth vs. Truth »

 

Before I even knew there was such a thing as DSD, I heard the effect when comparing DVD-A to SACD and always seemed to prefer the SACD version of the same title.

My universal player is set to bitstream output, and my AVR tells me it's Pure DSD.
Mostly I am listening via PS3-ripped dsf files streamed and AVR tells me it's Pure DSD.
Also listen to the dsf files on my Pono.

Again, the realism creeps up on you and once you realize/hear the effect it's tough to un-hear it.

 

And then your AVR converts it to PCM

 

Mebbe. Not all of them.

 

I do not think that is true.
While playing in Pure mode, the remote app and on-screen display reads DSD 2.8224 MHz
IF the AVR is not set to Pure Direct, DSD files do not play.

From my Marantz SR6009 manual...

Press PURE to select “Direct”.
Direct playback begins.
0 While DSD signals are played back, “DSD Direct” is displayed.

Also from the manual:
Supported audio formats
2-channel Linear PCM 2-channel, 32 kHz – 192 kHz, 16/20/24 bit
Multi-channel Linear
PCM 7.1-channel, 32 kHz – 192 kHz, 16/20/24 bit
Bitstream Dolby Digital / DTS / Dolby TrueHD / Dolby Digital Plus / DTS-HD Master Audio / DTS-HD High Resolution Audio / DTS Express
DSD 2-channel – 5.1-channel, 2.8224 MHz

 

Nope. Some will, but others will decode the DSD stream directly. Mine takes the DSD stream from my Cambridge Audio 752BD via HDMI.

 

Most of these things are doable in native DSD now.

 

Good f--king grief!!

I don't think I have ever seen more errors in a single article. The stream of conscience writing style was bad enough, but the guy gets virtually everything wrong.

Avoid, unless you have a technical background and need a good laugh!