Everything you need to know about DSD...
There seems to be an awful lot of confusion about this.
(And I've personally never understood the obsession with DSD to begin with - it is simply another digital audio format).
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In case you didn't realize it.... DSD is a digital audio FORMAT.... and is the format used on SACD DISCS.
SACD discs contain digital audio in the DSD format.
Hybrid SACD discs contain both a layer which contains audio in the DSD format and another layer that contains a copy in the regular Red Book CD format.
Some players can play both (and some let you choose which to listen to) - while regular CD players can only play the Red Book CD layer.
The DSD format is also used for music you can download... and there are several different "flavors" - including DSD, DXF, DSF, DFF, and DSDIFF.
(Which particular ones your player or software supports is up to it.... and all can be output as "DSD")
SACD discs and DSD files can be stereo or surround sound (5.1 channels) - or can contain tracks in both.
DSD files can also come in different "speeds" - which are the equivalent of different sample rates.
All SACDs contain "single speed DSD" (sometimes referred to as "DSD64" - which refers to the bit rate - which is 2.8224 mHz).
DSD files can also be recorded at higher sample rates (most commonly DSD128, which is sometimes called "double-rate DSD" or DSDx2, and DSD256, which is sometimes called "quad DSD" or DSDx4).
These are not as widely supported.
1)
The RMC-1, the RMC-1L, the XMC-2, and the XMC-1, ALL support DSD via HDMI natively.
What this means is that, if your source sends us DSD, we will accept it, and we will not convert it to PCM along the way.
(Since the DAC chips we use actually accept DSD, it will be routed straight to them without being converted to PCM).
(The XMC-1 supports only DSD64; the others of ours also support DSD128; none of ours support quad DSD).
2)
Some OTHER DAC chips simply do not have an input that accepts DSD directly (or, if they do, it isn't connected).
If a processor uses DACs that don't accept DSD, that processor may accept DSD, but convert it internally into PCM, and then send that PCM to their DACs.
(Or they may simply not accept DSD at all.)
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If you actually have a processor that doesn't accept DSD at all, many source devices that can play SACDs and DSD files will convert it into PCM themselves, and send that instead.
(And, if so, they may or may not tell you it's being converted.)
(Our processors will actually tell you, on their display, if we are receiving a DSD audio signal.)
4)
In general, these days, if your disc player can play SACDs, and it can play files, then it can also play the various types of DSD files you can download.
(This includes Oppo players, some Sonys, and a few others... although a lot of players DO NOT support SACDs nor DSD files.)
Whether your player can play DSD files, whether it will output the result as DSD, or whether it will convert it to PCM before sending it out, is strictly up to your player.
(Many players can be configured to do their best to output DSD if your processor supports it; but many cannot.)
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This is all ENTIRELY DIFFERENT than the ability to output or accept DSD via a USB connection.
That uses a whole separate standard - which may or may not be supported by your disc player or other source and may or may not be supported by your processor.
(The standard is called "DoP" - which stands for "DSD-over-PCM" - which can, at least theoretically, also be done over connections other than USB.)
Many computer-based player programs support DoP - including Foobar2000 and jRiver Media Center - although it may require special configuration or special drivers to get it to work.
VERY few hardware players currently support DoP (I don't know of one - but I'm sure there are a few.)
The XMC-1 does NOT support DSD via DoP (USB).
The XMC-2, RMC-1, and RMC-1L DO support DoP via USB - up to and including double speed (although we haven't tested it extensively yet and nobody has been asking about it).
6)
This is a slightly different discussion than the one about "whether certain DACs support DSD natively internally".
THAT discussion has gotten really confusing - and is related to the idea that any sort of conversion between audio formats is bad and is likely to degrade the sound.
(And this is especially considered to be an issue by fans of DSD - who are quite convinced that DSD sounds better than PCM and so converting it to PCM and back again is a terrible thing to do.
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Here are the facts there:
The way in which DSD signals are stored and processed is very much like the way D-S (delta-sigma) DACs work internally - and very much UNLIKE the way R2R DACs work internally.
(A DSD signal is very similar to one of the signals used internally in all D-S DACs ..... so the processes involved in playing a DSD signal are less complicated.)
Therefore, it can reasonably be said that "the processes involved in playing a DSD file on a D-S DAC relatively simple"....
And it can be said that, when playing a PCM file with a D-S DAC, the D-S DAC "has to do more work to convert and play it" and that "more complex conversions are involved"....
And it can also be said that "if you play a DSD file on a D-S DAC, but convert it to PCM along the way, you are "doing a lot of extra work" and that you've "done a lot of unnecessary conversions back and forth".
And, from all that, it follows that.....
- if you have a DSD file, convert it to PCM to send it to your processor, then play it using a D-S DAC, "you've done a lot of unnecessary conversions back and forth that may well degrade the sound quality"
- if you have a DSD file, and you instead leave it as DSD, and play it using a processor that natively supports DSD, you will avoid all of those potential issues
(Of course, being able to do this requires that all of your devices be willing to handle the DSD format itself, and that the DAC chips you use actually have a physical "DSD input".)
Sabre DACs use their own proprietary conversion process, which involves some complicated processing during the upsampling process to re-clock the signal and remove jitter.
(To many DSD fans who consider themselves to be audio purists this is sort of the antithesis of "directly converting the signal without messing with it".)
So hopefully we'll see these updates by 2021!
Wait a minute, does that mean the currently RMC-1 does not support DSD natively over HDMI?? If so, will this be a hardware upgrade or software?
When you go over them one by one ; they don't look too complex compared to say Dirac . As dts is already licensed dts-x pro coding is just an extra dsp mode enabling more than 7.1.4, EARC just means the hdmi chipset has been preprogrammed for it like other brands[ very important with streaming nevertheless]; USB multichannel means the chipset chosen had more than stereo capability [unlike the USB IN THE XMC1]
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