[FredA]

I was curious about S/PDIF and I had to search for 2 hours to find a 75 ohm cable. Finally found it buried in a box. I haven't listened to S/PDIF on Audio GD DACs in many years. On the R7 w. Asy3, S/PDIF doesn't sound bad but I2S wins with more dynamics, stage, and pop. Easy direct comparison switching between Inputs 3 and 5 driven by the SU-6. Give it a listen if you can find a cable!

The sound quality is why everyone uses HDMI I2S on Audio GD DACs, at least, the R2R-type DACs. Goes all the way back to Master 7 days.

I intend to try this at some point. Perhaps spidf is harder to dejitter? Or has more jitter in the first place? One way or the other, i2s seems to win most of the time, even with other cie's dacs, when offered.

 

[DACLadder]

SPDIF bi-phase mark encoding scheme encodes the clock in the bit stream. Traditionally a PLL is used to recover the clocks but with asynchronous firmware who knows for sure?

After doing S/PDIF testing and switching back to I2S my system is sounding as good as ever! The power grid must be light today!

 

[FredA]

SPDIF bi-phase mark encoding scheme encodes the clock in the bit stream. Traditionally a PLL is used to recover the clocks but with asynchronous firmware who knows for sure?

After doing S/PDIF testing and switching back to I2S my system is sounding as good as ever! The power grid must be light today!

Enjoy!

 

[comzee]

I intend to try this at some point. Perhaps spidf is harder to dejitter? Or has more jitter in the first place? One way or the other, i2s seems to win most of the time, even with other cie's dacs, when offered.

SPDIF bi-phase mark encoding scheme encodes the clock in the bit stream. Traditionally a PLL is used to recover the clocks but with asynchronous firmware who knows for sure?

Ya pretty much what @DACLadder said. The thing about spdif, is it needs to be converted to I2S anyway.
It's kinda like DDC-> SPDIF (PLL and other technical stuff) -> I2S -> DAC
Or DDC -> I2S -> DAC. You're completely cutting out a giant step of conversion and clocking, when you're trying to preserve a highly accurate bitperfect stream, I don't see how I2S couldn't be better, not just for AGD but for any DAC.
This is one of my biggest gripes about the Yggy, you're forced to use SPDIF in which in turn forces your bitperfect stream thru their "Adapticlock clock regeneration system". No bueno

 

[FredA]

Quick update on the M3:

After over 3 month and 700 or 800 hours of burn in, macrodynamics have much improved and are now satisfying all the time (plus i added a gauge 10 power cord to feed it today after trying other power cords, which improved things, read bigger is better). It is all i want from an amp. Except small. But it does not get much hotter than 30C.

It organic and smooth, while being neutral and transparent. As i read in a review, it is on the warm side of neutral. It can output harshness if fed with it, as it should. I am experimenting with an ocxo hooked up to my u16 with a badly put together bnc cable, which can make the r7he sound a little harsh at times. The m3 will play it through.

So i recommend the m3 without any reservation. The highs are really exceptional, the mids, splendid, the bass, tight and deep. You get attached to it with time, after the initial impression of having you living room invaded by it. Cheers to Kingwa and his team! Sometimes, bigger is better.

 

[Chopin75]

SPDIF bi-phase mark encoding scheme encodes the clock in the bit stream. Traditionally a PLL is used to recover the clocks but with asynchronous firmware who knows for sure?

After doing S/PDIF testing and switching back to I2S my system is sounding as good as ever! The power grid must be light today!

Wait, I thought the PLL won't affect the SPDIF/AES or may I mistaken somehow ?
The I2S direct is supposedly advantageous because the clock is separate from the audio signal.
Now I can see the advantage of source ---I2S---> DAC direct vs. Source ---SPDIF---> DAC direct.
But is there a clear advantage with : USB---> DDC---> I2S ----> DAC. vs SPDIF---> DAC direct. The latter is more simple, and assuming one uses a great SPDIF cable that is short enough. Perhaps the reclocking at the DDC is the main gain. How about an external clock at the SPDIF route too (like they used to do with CD transports) or a great clock at the SPDIF bridge.

 

[Chopin75]

That's interesting, seeing as I recently changed the firmware on the R8 and changed from hqplayer to MPD I thought I would compare some dsf songs from dire straits first album to the same songs converted to wav, and I thought PCM sounded better, it definitely had more dynamics, apart from that they were pretty similar, also my new favorite setting is MPD playing in bit perfect to the R8 in NOS mode with PLL activated on tda_syn, very natural sounding.

It also depends of whether the DSD recordings are original DSD or just converted from PCM to DSD. To take full advantage of DSD recordings it should be recorded originally as DSD with minimal or no PCM conversion during editing. So with these recordings, I can hear its high quality very easily. Converted DSD recordings are not really good in general (except some conversion from DXD ones are very good, from 2L). The PCM conversion usually gives a flatter/forward sound stage and "harder" & punchy sound, hence feels more dynamic. DSD has a more laid back sound stage relatively. So check of the recordings are made as original DSD or not. But I think most DSD recordings are classical and jazz/vocal mainly.

 

[guzz46]

It also depends of whether the DSD recordings are original DSD or just converted from PCM to DSD. To take full advantage of DSD recordings it should be recorded originally as DSD with minimal or no PCM conversion during editing. So with these recordings, I can hear its high quality very easily. Converted DSD recordings are not really good in general (except some conversion from DXD ones are very good, from 2L). The PCM conversion usually gives a flatter/forward sound stage and "harder" & punchy sound, hence feels more dynamic. DSD has a more laid back sound stage relatively. So check of the recordings are made as original DSD or not. But I think most DSD recordings are classical and jazz/vocal mainly.

Ok, that's me out of the DSD game then, seeing as most of my music is some form of pop, rock, hard rock, metal, sounds like PCM is better suited for kind of music anyway.

 

[Chopin75]

Happy to report that now after getting rid of the tube gain stage, outputting from the XLR is rather pleasant. There is more clarity/better sound stage and still having great analogue feel and not sounding shrill/digital. The smudge is gone and lower distortion (none if recordings are great). The tone is now more neutral, less colored without the tube stage, though also cooler but not cold. I have yet to see if the recordings are less than optimal, if I would need to add back the gain stage. The XLR output is something that really can help with the sound compared with unbalanced, though latter is also very good.

 

[davidnow]

Now I can see the advantage of source ---I2S---> DAC direct vs. Source ---SPDIF---> DAC direct.
But is there a clear advantage with : USB---> DDC---> I2S ----> DAC. vs SPDIF---> DAC direct. The latter is more simple, and assuming one uses a great SPDIF cable that is short enough. Perhaps the reclocking at the DDC is the main gain.

That is the point, i understand easily that when your source is USB, then USB -> DDC -> I2S is the shortest path. But if you can chose a SPDIF source, then SPDIF -> DAC -> I2S (inside the DAC) is as short as the previous path. The difference is USB <-> I2S conversion instead of SPDIF <-> I2S conversion. Then i wonder which process of conversion is the more efficient with audio data...

 

[Tango Sierra]

@DACLadder
I just saw that the other day you mentioned that you have purchased an Aurender N100H. Congratulations, you will not believe how much better it sounds than using your computer as a music server/renderer but it is very dependent on an upgraded power cord. At first, I wasn't so sure that the Aurender was all that much better until I tried an upgraded power cable. After living with it for three months now, using the computer to play files through my M7S sounds like chalk on a blackboard. The USB output of the Aurender is so good I have put off getting a converter for I2S and instead sent my phono cartridge in for repair so I can get my analog system up and running again.

 

[DACLadder]

The latter is more simple, and assuming one uses a great SPDIF cable that is short enough. Perhaps the reclocking at the DDC is the main gain. How about an external clock at the SPDIF route too (like they used to do with CD transports) or a great clock at the SPDIF bridge.

The beauty of S/PDIF is simplicity but notorious for jittery clocks. There have been proprietary S/PDIF + separate ext. clock designs in the past. Connect two coax cables in this case from a CD deck to DAC. Eliminates the PLL perhaps

 

[DACLadder]

@DACLadder
I just saw that the other day you mentioned that you have purchased an Aurender N100H. Congratulations, you will not believe how much better it sounds than using your computer as a music server/renderer but it is very dependent on an upgraded power cord. At first, I wasn't so sure that the Aurender was all that much better until I tried an upgraded power cable. After living with it for three months now, using the computer to play files through my M7S sounds like chalk on a blackboard. The USB output of the Aurender is so good I have put off getting a converter for I2S and instead sent my phono cartridge in for repair so I can get my analog system up and running again.

I'm certainly looking forward to the Aurender N100H. MY old PC's USB has not been the same since upgrading from Windows 8.1 to 10. Hopefully will arrive in two days!

 

[DACLadder]

Happy to report that now after getting rid of the tube gain stage, outputting from the XLR is rather pleasant. There is more clarity/better sound stage and still having great analogue feel and not sounding shrill/digital. The smudge is gone and lower distortion (none if recordings are great). The tone is now more neutral, less colored without the tube stage, though also cooler but not cold. I have yet to see if the recordings are less than optimal, if I would need to add back the gain stage. The XLR output is something that really can help with the sound compared with unbalanced, though latter is also very good.

Excellent! Time to upgrade the R2R 7! You told me you are going the full Magna cap/wiring upgrade! It will be a different DAC when you get it back.

 

[DACLadder]

I see my SU-6 supports DSD512 where the F1/SU-1 require a firmware upgrade. Only problem with testing DSD512 is I don't have any test files. Any place to download a small size DSD512 test file?