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Post by craigl59 on Oct 14, 2016 19:57:52 GMT -5
Regardless of method, the Cary has a fantastically convenient feature - One can select up-sampling frequency, DSD conversion / oversampling, etc. from the remote while the music is playing. Want to see how one sounds against the other? Swap 'em on the fly! What matters isn't necessarily what technology is being used, but what comes out the speakers. So far, I like the high frequency DSD the best (being unconverted from the TOSLINK 44.1 PCM stream). But I haven't given them all a fair shake yet - and there's more than a dozen options to choose from. Would be interested in your preferred choice along with adjectival descriptions as to how it was superior. Been up-sampling through JRiver (and the new SoX feature in version 22) for some time and am surprised at the improvement it makes (especially S/N). Am not knowledgeable about DSD formats partly because I have not heard any difference between it and 96/24 and partly because my DAWs have always used PCM processing. The information in this thread is very helpful and I wonder if anyone could describe to me more fully how DSD sounds more "analog-like." Does this mean smoother or boosted in some frequency range? Thanks in advance. There is a double-blind test done in 2004 in which listeners were unable to distinguish between DSD and PCM formats. Have there been improvements since then to DSD processing? Have an XMC-1 coming next week and will be connecting an Oppo 103D to it. Pardon me if this is an ignorant question but is it better to send a DSD/SACD signal to the XMC-1 for conversion or to run analog outputs from the Oppo to the XMC-1 for a pass through? |
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Post by geebo on Oct 14, 2016 20:05:26 GMT -5
You could send pure DSD files from a NAS using DLNA on the Oppo 105. We do it all the time! Yes. The question wasn't if Oppo can receive DSD data via DLNA streaming and play it natively, but rather, can Oppo transfer said data, without altering the bits of said data that is, into a separate DAC/receiver/prepro/device; the answer is "no way" because Oppo ain't a NAS or HTPC. It can do it over HDMI but not by any other means. |
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Post by yves on Oct 15, 2016 0:03:03 GMT -5
Yes. The question wasn't if Oppo can receive DSD data via DLNA streaming and play it natively, but rather, can Oppo transfer said data, without altering the bits of said data that is, into a separate DAC/receiver/prepro/device; the answer is "no way" because Oppo ain't a NAS or HTPC. It can do it over HDMI but not by any other means. Over HDMI, yes, but anything below HDMI ver. 2.0 is still altering the bits in some particular way (their timing). That's because the audio clock has to be derived from the TDMS (video) clock, and, with DSD (and Sigma Delta modulators) being sensitive to timing aberrations, it kind of defeats the whole purpose of using Oppo as a very high quality transport, which it clearly isn't... and that can completely be solved by building your own small HTPC on the cheap as long as your separate DAC uses the type of asynchronous USB input that doesn't give USB the bad name that USB has in audio land. |
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Post by solarrdadd on Oct 16, 2016 20:59:52 GMT -5
Some questions, please, gents - My understanding is that if I download a DSD file, and then play it through JRiver Media Center 22 - over Ethernet DLNA - to my Oppo BDP-105 that somewhere in the chain (Ethernet over DLNA?) the file is automatically converted back to PCM and that the stream that reaches the Oppo will no longer be a DSD file. True? Even if JRiver manages to get the file to the Oppo, I don't want it converted to analog there. Instead, I want it passed through its coaxial digital output to the Schiit Gungnar Multibit OR to the Cary SI-300.2D (both of which can do DSD conversion without reverting to PCM). Will the Oppo pass DSD streams without conversion? Finally, the Cary has the potential to convert PCM streams to DSD. Why would there be any advantage to this? It would seem that one could never get higher quality than the PCM file one started with, regardless of additional processing. True or false? Pardon my ignorance, but before I spend half a day doing internet research I thought I'd "ask-the-experts." Thanks - Boomzilla at home, I have DSD files on a NAS and I stream them to my 105 and they are not converted to PCM but stream as DSD straight to the DAC. there is a setting in the oppo that says play DSD straight or convert to PCM you should check to make sure what it's set to. also, check to make sure you don't have JRiver set to convert the DSD to PCM because I believe there is also a setting for that in JRiver. when I stream at home, it's just pure data from the NAS, there is no JRiver or anything. the 105 sees the folder labled DSD under Public Music and streams the files to it. good luck boomzilla! |
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Post by geebo on Oct 16, 2016 21:06:19 GMT -5
Some questions, please, gents - My understanding is that if I download a DSD file, and then play it through JRiver Media Center 22 - over Ethernet DLNA - to my Oppo BDP-105 that somewhere in the chain (Ethernet over DLNA?) the file is automatically converted back to PCM and that the stream that reaches the Oppo will no longer be a DSD file. True? Even if JRiver manages to get the file to the Oppo, I don't want it converted to analog there. Instead, I want it passed through its coaxial digital output to the Schiit Gungnar Multibit OR to the Cary SI-300.2D (both of which can do DSD conversion without reverting to PCM). Will the Oppo pass DSD streams without conversion? Finally, the Cary has the potential to convert PCM streams to DSD. Why would there be any advantage to this? It would seem that one could never get higher quality than the PCM file one started with, regardless of additional processing. True or false? Pardon my ignorance, but before I spend half a day doing internet research I thought I'd "ask-the-experts." Thanks - Boomzilla at home, I have DSD files on a NAS and I stream them to my 105 and they are not converted to PCM but stream as DSD straight to the DAC. there is a setting in the oppo that says play DSD straight or convert to PCM you should check to make sure what it's set to. also, check to make sure you don't have JRiver set to convert the DSD to PCM because I believe there is also a setting for that in JRiver. when I stream at home, it's just pure data from the NAS, there is no JRiver or anything. the 105 sees the folder labled DSD under Public Music and streams the files to it. good luck boomzilla! But the Oppo cannot pass DSD out over anything but HDMI. He was wanting to use coax to pass DSD from the Oppo to another DAC outside the Oppo. |
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Post by solarrdadd on Oct 16, 2016 21:16:09 GMT -5
at home, I have DSD files on a NAS and I stream them to my 105 and they are not converted to PCM but stream as DSD straight to the DAC. there is a setting in the oppo that says play DSD straight or convert to PCM you should check to make sure what it's set to. also, check to make sure you don't have JRiver set to convert the DSD to PCM because I believe there is also a setting for that in JRiver. when I stream at home, it's just pure data from the NAS, there is no JRiver or anything. the 105 sees the folder labled DSD under Public Music and streams the files to it. good luck boomzilla! But the Oppo cannot pass DSD out over anything but HDMI. He was wanting to use coax to pass DSD from the Oppo to another DAC outside the Oppo. I think I read the OP in post #1 and then saw his post and didn't catch the part about using Digital Coax. can't stream DSD over that anyway. so, you are correct about the Oppo & HDMI as far as passing DSD. again, got caught up mostly with the OP's 1st post. thanks geebo. |
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Post by geebo on Oct 16, 2016 21:49:33 GMT -5
But the Oppo cannot pass DSD out over anything but HDMI. He was wanting to use coax to pass DSD from the Oppo to another DAC outside the Oppo. I think I read the OP in post #1 and then saw his post and didn't catch the part about using Digital Coax. can't stream DSD over that anyway. so, you are correct about the Oppo & HDMI as far as passing DSD. again, got caught up mostly with the OP's 1st post. thanks geebo. And your point about streaming DSD direct to the Oppo is also valid. I do that myself. He'd just have to convert direct from DSD to anaolog in the Oppo if he wants to avoid the intermediate PCM stage. |
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Post by yves on Oct 17, 2016 7:28:10 GMT -5
I think I read the OP in post #1 and then saw his post and didn't catch the part about using Digital Coax. can't stream DSD over that anyway. so, you are correct about the Oppo & HDMI as far as passing DSD. again, got caught up mostly with the OP's 1st post. thanks geebo. And your point about streaming DSD direct to the Oppo is also valid. I do that myself. He'd just have to convert direct from DSD to anaolog in the Oppo if he wants to avoid the intermediate PCM stage. Either that, or get a (much) better sounding DAC than the Oppo Blu-ray player's built-in one........  |
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Post by Wideawake on Oct 17, 2016 12:44:42 GMT -5
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KeithL
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Post by KeithL on Oct 17, 2016 13:55:44 GMT -5
I'm not sure you've actually got the details right (you might have), but doing it that way doesn't really make a lot of sense...... The sound starts out in analog... Then it gets converted into digital to be recorded... Then it gets converted back into analog to be edited... Then it gets converted back into digital again after being edited.... Then back into analog yet AGAIN to go to an amp, and speakers.... If you count up the conversions between analog and digital you'll find FOUR of them.... Since every conversion entails some loss of quality, one generally tries to minimize them whenever possible. This only makes sense if YOU'RE SPECIFICALLY LOOKING FOR ALL THE COLORATIONS ASSOCIATED WITH THE VARIOUS CONVERSIONS AND STOPS ALONG THE WAY. In other words, if you like the way a certain recorder "sounds", and the way a certain mixing board or certain FX plugins "sound". However, if you're looking for an accurate and neutral rendition, then this is about as far from that as you can possibly get. I'll bet that, somewhere, there is some great author who still writes all his novels on an old Remington manual typewriter..... or even with a "#2 pencil"..... And they may do great work with their old favorite writing utensil, and be very fond of it..... but I don't take that to mean that #2 pencils or manual typewriters "do a better job than a word processor" in the more general sense. I understand that DSD is as close to analog as you can get in the digital world. But studios don't record in DSD they record in 24bit 192kHz. I am assuming that the DAW would also be working at this so that no transcoding is done during the mix. So what would be any benefit to later converting to DSD? Cookie Morenco records in DSD. Edits in analog. |
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Post by solidstate on Oct 17, 2016 14:09:15 GMT -5
It can do it over HDMI but not by any other means. Over HDMI, yes, but anything below HDMI ver. 2.0 is still altering the bits in some particular way (their timing). That's because the audio clock has to be derived from the TDMS (video) clock, and, with DSD (and Sigma Delta modulators) being sensitive to timing aberrations, it kind of defeats the whole purpose of using Oppo as a very high quality transport, which it clearly isn't... and that can completely be solved by building your own small HTPC on the cheap as long as your separate DAC uses the type of asynchronous USB input that doesn't give USB the bad name that USB has in audio land. hmm... interesting point. Somebody needs to design a PCIe based AES/EBU device with DoP that connects to a PC via Thunderbolt or USB 3.1 (supports two PCIe lanes) perhaps negating this issue. Great thing is the XMC-1 has AES/EBU input! MADI is also an interesting possible solution. I'd like to see processor makers design a pre/pro that has MADI out and a second chassis with the converter section. That or simply pass IIS/I2S out to a box specifically to be used as a converter only. The second converter/analog section chassis would allow much more space on PCB to have proper balanced outs on all channels and a really great I/V and line driver for each channel. There is no reason why you can't pass multiple IIS/I2S buses a short distance via an HDMI connector between these two proposed devices. PS I heard recent testimony here that a certain DAC sounded much better via AES/EBU transport vs. USB |
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Post by jmilton on Oct 17, 2016 14:18:42 GMT -5
Going from DSD to analog and back does not degrade the signal. Downsampling damages the signal. You can copy a CD a thousand times and copy 1 will be identical to copy 1,000 (provided your copy device is not defective, in which case you have drop-outs).As you lose bits, the loss is on the quietest sounds, not the loudest. This could be the opposite, but the way digital audio systems are set up if you record something at 20 bits and then lop off 4 of those bits later on, the loudest signals present are untouched but the quietest signals are just gone – so you would go from 120dB of range (between the loudest to the softest) to 96dB – but the loudest would remain the same.
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Post by solidstate on Oct 17, 2016 14:21:01 GMT -5
I'm not sure you've actually got the details right (you might have), but doing it that way doesn't really make a lot of sense...... The sound starts out in analog... Then it gets converted into digital to be recorded... Then it gets converted back into analog to be edited... Then it gets converted back into digital again after being edited.... Then back into analog yet AGAIN to go to an amp, and speakers.... If you count up the conversions between analog and digital you'll find FOUR of them.... Since every conversion entails some loss of quality, one generally tries to minimize them whenever possible. This only makes sense if YOU'RE SPECIFICALLY LOOKING FOR ALL THE COLORATIONS ASSOCIATED WITH THE VARIOUS CONVERSIONS AND STOPS ALONG THE WAY. In other words, if you like the way a certain recorder "sounds", and the way a certain mixing board or certain FX plugins "sound". However, if you're looking for an accurate and neutral rendition, then this is about as far from that as you can possibly get. I'll bet that, somewhere, there is some great author who still writes all his novels on an old Remington manual typewriter..... or even with a "#2 pencil"..... And they may do great work with their old favorite writing utensil, and be very fond of it..... but I don't take that to mean that #2 pencils or manual typewriters "do a better job than a word processor" in the more general sense. Cookie Morenco records in DSD. Edits in analog. Edits in analog? Bizarre! I guess that's a way to avoid DXD conversions... LOL Or perhaps Cookie isn't aware of Pyramix or Serenade? PS prob using old reel tape recorders LMAO |
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Post by solidstate on Oct 17, 2016 14:24:53 GMT -5
Yeah well I guess I should shut my mouth with her Grammies, Gold records and Academy Award eh!
Still I think her Extended Sound Environment (E.S.E.) thing is TOTAL BS...
PS she's using Ed's (EMMlabs) converters
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Post by solidstate on Oct 17, 2016 14:30:05 GMT -5
Going from DSD to analog and back does not degrade the signal. Downsampling damages the signal. You can copy a CD a thousand times and copy 1 will be identical to copy 1,000 (provided your copy device is not defective, in which case you have drop-outs).As you lose bits, the loss is on the quietest sounds, not the loudest. This could be the opposite, but the way digital audio systems are set up if you record something at 20 bits and then lop off 4 of those bits later on, the loudest signals present are untouched but the quietest signals are just gone – so you would go from 120dB of range (between the loudest to the softest) to 96dB – but the loudest would remain the same. Wha? I pad 16 bit audio to 24 bit for digital attenuation all the time and no the quietest signals are not "just gone". Also your analogy is totally flawed when speaking of CD duplication as it remains in the digital domain. I agree with KeithL 100% and I think Cookie and Jean are totally nuts man... I think all of this recent tape stuff is TOTAL BULLSHIT just like I think LPs are a joke... But hey that's just one man's opinion. PS correct they have been NOMINATED for a Grammy a number of times but didn't actually win |
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Post by jmilton on Oct 17, 2016 14:57:29 GMT -5
It can do it over HDMI but not by any other means. Over HDMI, yes, but anything below HDMI ver. 2.0 is still altering the bits in some particular way (their timing). That's because the audio clock has to be derived from the TDMS (video) clock, and, with DSD (and Sigma Delta modulators) being sensitive to timing aberrations, it kind of defeats the whole purpose of using Oppo as a very high quality transport, which it clearly isn't... and that can completely be solved by building your own small HTPC on the cheap as long as your separate DAC uses the type of asynchronous USB input that doesn't give USB the bad name that USB has in audio land. DoP can be done other than HDMI. McGowan explains it as such: The PCM format uses a series of frames, or snapshots, for the data. Each frame is a separate grouping of audio containing a left and right sample. In a CD we get samples of the music and each sample is taken 44,000 times per second, once for the left channel and again for the right channel (so the process happens twice as fast in order to get two 44K samples in the same time). Now, mentally take those two samples (left and right) and put them into a package. That’s the frame we are talking about in PCM. Each frame contains one left and one right sample along with some extra information that explains to the equipment what to expect. The DSD format, on the other hand, does not have any frames; instead it is a steady stream of bits with more or less density according the the music. So here’s the clever thing the designers of DoP did. They simply took the DSD stream apart into discrete 16 bit groups; every 16 bit block was separated from the stream. They then combined a 16 bit right group together with a 16 bit left group, added the identifier information and dressed it up so computers and DACS would think it’s PCM. As far as any computers or USB streams are concerned, it is indistinguishable from PCM so it is passed onto the DAC via USB, S/PDIF or AES/EBU. Very clever indeed. To match the speed of single and double DSD, they use 176.4kHz and 352.8kHz PCM rates respectively. Once it gets to the DAC, it is then converted back to its original stream by simply connecting all the bits back together. There’s no data manipulation, the bits are unscathed and, if your DAC can play DSD you’re good to go. If the DAC does not support DSD, you get silence. |
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Post by yves on Oct 17, 2016 15:43:12 GMT -5
Over HDMI, yes, but anything below HDMI ver. 2.0 is still altering the bits in some particular way (their timing). That's because the audio clock has to be derived from the TDMS (video) clock, and, with DSD (and Sigma Delta modulators) being sensitive to timing aberrations, it kind of defeats the whole purpose of using Oppo as a very high quality transport, which it clearly isn't... and that can completely be solved by building your own small HTPC on the cheap as long as your separate DAC uses the type of asynchronous USB input that doesn't give USB the bad name that USB has in audio land. hmm... interesting point. Somebody needs to design a PCIe based AES/EBU device with DoP that connects to a PC via Thunderbolt or USB 3.1 (supports two PCIe lanes) perhaps negating this issue. Great thing is the XMC-1 has AES/EBU input! MADI is also an interesting possible solution. I'd like to see processor makers design a pre/pro that has MADI out and a second chassis with the converter section. That or simply pass IIS/I2S out to a box specifically to be used as a converter only. The second converter/analog section chassis would allow much more space on PCB to have proper balanced outs on all channels and a really great I/V and line driver for each channel. There is no reason why you can't pass multiple IIS/I2S buses a short distance via an HDMI connector between these two proposed devices. PS I heard recent testimony here that a certain DAC sounded much better via AES/EBU transport vs. USB The problem of HDMI-CEC Audio Clock Regenreration (ACR) has been explained in this presentation: Audio Transport over HDMI—How good do you want it to sound?www.aes-media.org/sections/uk/Conf2011/Presentation_PDFs/14%20-%20john%20dawson%20-%20Audio%20Transport%20over%20HDMI%20-%20AES%202011.pdfAsynchronous USB already solves a similar problem inherent of AES/EBU and S/PDIF... but IMHO asynchronous USB has been given a serious bad name by a lot of manufacturers who either can't understand how electric noise and electromagnetic interference (EMI) can propagate from the USB input interface module into the more sensitive parts of a DAC unit, or basically just want to skimp on the USB implementation because doing that will save them some extra money. Is the AES/EBU/SPDIF Digital Audio Interface Flawed?www.aes.org/e-lib/browse.cfm?elib=6773 |
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KeithL
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Post by KeithL on Oct 17, 2016 15:52:47 GMT -5
Actually, it's the SACD license that doesn't allow SACD players to export a full quality digital audio signal from an SACD over a digital output that isn't "secure" (HDMI is secure). However, that requirement is part of the SACD copy protection scheme, and goes with the SACD media in specific..... DSD audio that originates from something else, for example a file, doesn't have that restriction. (I have no idea how the individual players may feel about it - or whether they make the distinction.) The discussion has already been done to death, but DSD itself has no compelling technical advantages over PCM. DSDx1 is superior in some technical details over the 16/44k PCM used on CDs - but not over 24/96k PCM. In general, as a RECORDING and REPRODUCTION medium, DSD is about equal to PCM, and it's about equally difficult to convert into analog when you want to play it. However, since it has severe limitations in regard to editing, it has never made it as an editing standard, and has been a commercial failure as a distribution medium as well. (Sony has made the DSD format license available to all comers for free - we can assume they did this because it wasn't making them any money.) However, the hardware in a given DAC may be optimized to do a better job with one or the other. So, for that particular DAC, it may make sense to convert all incoming signals to the format it prefers. (It should be possible to design a DAC that will work equally well with both - but that doesn't mean that all of them are.) You also need to understand that ANY time you convert between sample rates or formats you introduce tiny differences to the signal. Furthermore, there are usually choices involved, which involve tradeoffs, any of which may or may not be slightly audible. However, in most cases, these changes aren't better or worse - just different. (And, since certain tradeoffs may suit your personal preference better, or work better with certain source material, choices can be useful.) Another factor is that SACDs are mastered with a different target audience in mind. People who buy SACDs and DSD files expect "a more audiophile sound" - whatever that means to them and the engineer who mastered the disc. There is also different technology involved - SACD mastering offers less flexibility and fewer options. All of these factors lead to the fact that it isn't unusual at all for the SACD version of an album to be mastered differently than the PCM version. And all of this leads back to the question of what exactly you mean by "quality". To answer that original question...... Since information cannot be created, if by "quality" you mean "information accurate to the original", then NOTHING can give you more quality than was there in the original file. At most, by converting to some specific format or sample rate, you may be allowing a specific DAC to do a better job of causing less damage to the information that is present. (This is why most modern DACs do internal oversampling; because the oversampled signal can be converted more accurately with less alteration by the reconstruction filters.) And, since each conversion may alter the sound a little bit, you may simply like the way audio sounds after being passed through a certain conversion process. (And it's the job of the marketing department at any company to convince you that the differences in their product make it better.  And, if you're the type of person who simply likes more choices, and more options to choose from, then DSD is simply one more option to choose from. I should also note that you need to be careful when reading white papers..... many of them are quite old and digital audio technology changes quite rapidly. One of the linked white papers compared DSD with single-bit Delta-Sigma converters.... but virtually all modern DACs use multi-bit Delta-Sigma converters. Likewise, it used to be common to compare SACDs to CDs (DSDx1 to 16/44k PCM); but high-resolution 24/96k PCM audio files are becoming quite common these days. It is my understanding that the Oppo CAN receive DSD via DLNA (over Ethernet)... And this is claimed to work with some DLNA servers (perhaps some versions of Twonky). However, I've read that it won't work with jRiver. (If you Google "Oppo DSD DLNA" you can find a lot of discussion and suggestions on the subject...) You could try HERE for starters: www.computeraudiophile.com/f22-networking-networked-audio-and-streaming/oppo-bdp-10%5B3-5%5D-d-and-multichannel-direct-stream-digital-playback-26808/Some questions, please, gents - My understanding is that if I download a DSD file, and then play it through JRiver Media Center 22 - over Ethernet DLNA - to my Oppo BDP-105 that somewhere in the chain (Ethernet over DLNA?) the file is automatically converted back to PCM and that the stream that reaches the Oppo will no longer be a DSD file. True? Even if JRiver manages to get the file to the Oppo, I don't want it converted to analog there. Instead, I want it passed through its coaxial digital output to the Schiit Gungnar Multibit OR to the Cary SI-300.2D (both of which can do DSD conversion without reverting to PCM). Will the Oppo pass DSD streams without conversion? Finally, the Cary has the potential to convert PCM streams to DSD. Why would there be any advantage to this? It would seem that one could never get higher quality than the PCM file one started with, regardless of additional processing. True or false? Pardon my ignorance, but before I spend half a day doing internet research I thought I'd "ask-the-experts." Thanks - Boomzilla You can't send DSD over coax or Toslink. DSD licensing doesn't allow for it. The Oppo can send DSD via HDMI, however. |
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KeithL
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Post by KeithL on Oct 17, 2016 16:01:00 GMT -5
I would add one clarification to the terminology involved....... The term DoP refers to "DSD-over-PCM".... which is a sort of standard. Sending DSD over HDMI isn't termed as DoP...... (I don't know what's going on inside the signal itself). Our XMC-1 can cheerfully accept DSD via HDMI (like from an Oppo). However, our XMC-1 does NOT accept DSD over USB (and we do NOT support DoP). It's quite possible for a source device to support DSD over HDMI, and audio over USB, but NOT DSD audio over USB (DoP). If you want a DAC or a player program that supports DoP, you need to SPECIFICALLY look for that on the specs. Over HDMI, yes, but anything below HDMI ver. 2.0 is still altering the bits in some particular way (their timing). That's because the audio clock has to be derived from the TDMS (video) clock, and, with DSD (and Sigma Delta modulators) being sensitive to timing aberrations, it kind of defeats the whole purpose of using Oppo as a very high quality transport, which it clearly isn't... and that can completely be solved by building your own small HTPC on the cheap as long as your separate DAC uses the type of asynchronous USB input that doesn't give USB the bad name that USB has in audio land. DoP can be done other than HDMI. McGowan explains it as such: The PCM format uses a series of frames, or snapshots, for the data. Each frame is a separate grouping of audio containing a left and right sample. In a CD we get samples of the music and each sample is taken 44,000 times per second, once for the left channel and again for the right channel (so the process happens twice as fast in order to get two 44K samples in the same time). Now, mentally take those two samples (left and right) and put them into a package. That’s the frame we are talking about in PCM. Each frame contains one left and one right sample along with some extra information that explains to the equipment what to expect. The DSD format, on the other hand, does not have any frames; instead it is a steady stream of bits with more or less density according the the music. So here’s the clever thing the designers of DoP did. They simply took the DSD stream apart into discrete 16 bit groups; every 16 bit block was separated from the stream. They then combined a 16 bit right group together with a 16 bit left group, added the identifier information and dressed it up so computers and DACS would think it’s PCM. As far as any computers or USB streams are concerned, it is indistinguishable from PCM so it is passed onto the DAC via USB, S/PDIF or AES/EBU. Very clever indeed. To match the speed of single and double DSD, they use 176.4kHz and 352.8kHz PCM rates respectively. Once it gets to the DAC, it is then converted back to its original stream by simply connecting all the bits back together. There’s no data manipulation, the bits are unscathed and, if your DAC can play DSD you’re good to go. If the DAC does not support DSD, you get silence. |
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Post by yves on Oct 17, 2016 16:03:51 GMT -5
Over HDMI, yes, but anything below HDMI ver. 2.0 is still altering the bits in some particular way (their timing). That's because the audio clock has to be derived from the TDMS (video) clock, and, with DSD (and Sigma Delta modulators) being sensitive to timing aberrations, it kind of defeats the whole purpose of using Oppo as a very high quality transport, which it clearly isn't... and that can completely be solved by building your own small HTPC on the cheap as long as your separate DAC uses the type of asynchronous USB input that doesn't give USB the bad name that USB has in audio land. DoP can be done other than HDMI. McGowan explains it as such: The PCM format uses a series of frames, or snapshots, for the data. Each frame is a separate grouping of audio containing a left and right sample. In a CD we get samples of the music and each sample is taken 44,000 times per second, once for the left channel and again for the right channel (so the process happens twice as fast in order to get two 44K samples in the same time). Now, mentally take those two samples (left and right) and put them into a package. That’s the frame we are talking about in PCM. Each frame contains one left and one right sample along with some extra information that explains to the equipment what to expect. The DSD format, on the other hand, does not have any frames; instead it is a steady stream of bits with more or less density according the the music. So here’s the clever thing the designers of DoP did. They simply took the DSD stream apart into discrete 16 bit groups; every 16 bit block was separated from the stream. They then combined a 16 bit right group together with a 16 bit left group, added the identifier information and dressed it up so computers and DACS would think it’s PCM. As far as any computers or USB streams are concerned, it is indistinguishable from PCM so it is passed onto the DAC via USB, S/PDIF or AES/EBU. Very clever indeed. To match the speed of single and double DSD, they use 176.4kHz and 352.8kHz PCM rates respectively. Once it gets to the DAC, it is then converted back to its original stream by simply connecting all the bits back together. There’s no data manipulation, the bits are unscathed and, if your DAC can play DSD you’re good to go. If the DAC does not support DSD, you get silence. Both my Eastern Electric MiniMax DAC Supreme, which I purchased new in November 2014, and my Astell & Kern AK240, which I purchased new in August 2014, can support native DSD up to 128fs. The MiniMax Supreme uses DoP for native DSD playback so for more than a reasonable period of time I have already been having first hand practical/listening experience with both native DSD and native DSD via DoP... that's why almost two years ago I already knew about the principle behind DoP... |
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