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I2S via HDMI pinout wiring.

gallantus

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Hi Everyone,

Need some help here.

First some bullet points on the background of the situation:
  1. SACD players are intentionally designed to not send DSD signals via the digital output for copyright purposes. However, some SACD players can send the DSD signal via video HDMI, not to be confused with I2S HDMI. But DACs do not accept DSD signals via a video HDMI, it only accepts it through either USB, I2S ethernet or I2S HDMI.
  2. There exist a product where it can extract the digital audio stream (both PCM and DSD) out of the video HDMI and output the PCM stream via optical, digital coaxial and I2S HDMI or the DSD stream via I2S HDMI. This is the such product: HDMI/MHL To I2S IIS HDMI IIS I2S Dual-Mode Digital Audio I2S/Optical/DSD/Coaxial | eBay
  3. As you all may already know, there are no standards with I2S wiring via HDMI (nor for ethernet for that matter). So one would need to make sure that the I2S HDMI wiring of the source and the DAC matches to ensure that it works.
  4. I contacted the seller of said product from bullet point (2) and the seller provided me the I2S HDMI wiring diagram. As it is turns out, it is not compatible with my LKS MH-DA004 DAC. As such, I plan to build my own HDMI cable (using a solderless HDMI adaptor in the picture below) to match up the pins.
The help I am asking for is: Can someone (maybe an practicing electrical engineer) confirm for me that my diagram below will work and is safe? Please note that "NC" means, no connection, that the pin is not used. Also, it would be great if someone can explain the difference between ground and no connection in I2S HDMI.

Thank you all in advance for your help, much appreciate it.
 

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gvl

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I'm not a practicing EE but this looks reasonable assuming the DSD flag is compatible between devices. I tend to think you should be able to do away with just one ground connection say 17 to 19. And make the cable as short as possible.

As a side note, there's no objective data that confirms how well these extractors work with various DACs. For all I know a SPDIF connection from your SACD player into the DAC may well be technically superior despite the DSD to PCM conversion.
 
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Kal Rubinson

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SACD players are intentionally designed to not send DSD signals via the digital output for copyright purposes. However, some SACD players can send the DSD signal via video HDMI, not to be confused with I2S HDMI. But DACs do not accept DSD signals via a video HDMI, it only accepts it through either USB, I2S ethernet or I2S HDMI.
Some do.
 
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gallantus

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Interesting. Those SACD players must use a I2S output for DSD then as my understanding is that optical, digital coaxial, BNC does not have sufficient bandwidth to support DSD (maybe two channel, but not multi-channel). And if that is the case, then I would still have this problem as I2S HDMI wiring has no industry standard.
 

gvl

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It's DSD over HDMI proper. As long as you have encryption in place and paid all the licensing fees there's no technical reason you can't have it on a (expensive) DAC, eg Bryston BDA-3.

Edit: actually Essence HDACC-II can do it too, and it's $649 so not too bad. But as far as DACs go it's nothing to write home about except it's features.
 
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Kal Rubinson

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Interesting. Those SACD players must use a I2S output for DSD then as my understanding is that optical, digital coaxial, BNC does not have sufficient bandwidth to support DSD (maybe two channel, but not multi-channel). And if that is the case, then I would still have this problem as I2S HDMI wiring has no industry standard.
No. What I am saying is that some DACs do accept DSD signals via a video HDMI.
 
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gallantus

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No. What I am saying is that some DACs do accept DSD signals via a video HDMI.
Interesting, most A/V receivers that can decode DSD will do DSD over video HDMI. Are there dedicated two channel DACs that can do DSD over video HDMI?

I'm a two channel stereo guy for music, so any AV receivers is not in my purview.
 
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gallantus

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It's DSD over HDMI proper. As long as you have encryption in place and paid all the licensing fees there's no technical reason you can't have it on a (expensive) DAC, eg Bryston BDA-3.

Edit: actually Essence HDACC-II can do it too, and it's $649 so not too bad. But as far as DACs go it's nothing to write home about except it's features.
I was reading that the Essence model does DSD over DoP, so no DSD proper?
 
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gallantus

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The specs for the latest model say DSD over HDMI up to 256.
OK, well. . .I already have a DAC, so I won't be getting this. But for the vast majority of readers out there, chances are their DAC won't support DSD over video HDMI and chances are I2S HDMI is incompatible with many sources, unless they have a Topping that has multiple I2S HDMI configuration settings.
 

gvl

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If my SACD player could output 96khz PCM over SPDIF I'd just settle on that instead of trying to make unproven gizmos from ebay work with my DAC. Just my 2c.
 

Kal Rubinson

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Interesting, most A/V receivers that can decode DSD will do DSD over video HDMI. Are there dedicated two channel DACs that can do DSD over video HDMI?

I'm a two channel stereo guy for music, so any AV receivers is not in my purview.
Bryston comes to mind.
 
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gallantus

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If my SACD player could output 96khz PCM over SPDIF I'd just settle on that instead of trying to make unproven gizmos from ebay work with my DAC. Just my 2c.
This is fully proven to work and works very well. This device is actually fairly proliferated. The problem is, I just am not sure of my pin schematics.

I will be forging forward with this and will be able to get it to work, but dammit, I just want to get it right the first time around.
 

gvl

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This is fully proven to work and works very well. This device is actually fairly proliferated. The problem is, I just am not sure of my pin schematics.

I will be forging forward with this and will be able to get it to work, but dammit, I just want to get it right the first time around.

Thanks to @amirm we've seen dozens of devices that are proliferated and proven to work yet perform like crap on the test bench. It has been shown that clean clock extraction from HDMI is difficult and DAC performance over I2S is highly dependent on the clock quality. And what kind of quality of implementation can you expect from a $40 ebay solution? So in the end you may end up with a lower resolution signal on audio outputs with DSD than just using PCM/SPDIF or the player's internal DAC for that matter. It may seem like a good idea but unless you have a way to confirm the performance it's basically crapshoot.
 
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gallantus

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Thanks to @amirm we've seen dozens of devices that are proliferated and proven to work yet perform like crap on the test bench. It has been shown that clean clock extraction from HDMI is difficult and DAC performance over I2S is highly dependent on the clock quality. And what kind of quality of implementation can you expect from a $40 ebay solution? So in the end you may end up with a lower resolution signal on audio outputs with DSD than just using PCM/SPDIF or the player's internal DAC for that matter. It may seem like a good idea but unless you have a way to confirm the performance it's basically crapshoot.
Well let me ask this. If a DAC has it's own clock, is the bit stream still clocked at the source? That is a real question because I have heard regardless of the DAC clock, CD (and SACD) are still clocked at the transport. I have not been able to find any technical papers stating this claim.

However, I am suspecting that is not the case, my suspicion is that if a DAC has a clock the bit stream is clocked by the DAC. If that is the case, my DAC, LKS MH-DA004, has a very accurate clock.

And I don't subscribe to cost being the determining factor of a product's performance, as @amirm has proven time and time again.

So let's get someone with the technical authority to weigh in on this: If an external DAC has a clock, is the bit stream then clocked by the DAC or does it remain as it is clocked by the source.
 

gvl

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While it is true that ESS DACs that are in the LKS can and usually operate asynchronously on its own clock I don't know if the DAC chip in LKS runs asynchronously or synchronously over I2S. Even if it does run asynchronously from the source there are limits of what ASRC can do and bad incoming clock can still affect D/A conversion. For DSD however, the stability of the clock can be of lesser importance, not sure. It's all speculation and hand waving anyway, someone needs to take this HDMI extractor and feed it some test signals and analyze the analog output of a particular DAC to get an idea how well this solution performs as there can be other issues apart from the clock.
 

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linger63

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Hi Everyone,

Need some help here.

First some bullet points on the background of the situation:
  1. SACD players are intentionally designed to not send DSD signals via the digital output for copyright purposes. However, some SACD players can send the DSD signal via video HDMI, not to be confused with I2S HDMI. But DACs do not accept DSD signals via a video HDMI, it only accepts it through either USB, I2S ethernet or I2S HDMI.
  2. There exist a product where it can extract the digital audio stream (both PCM and DSD) out of the video HDMI and output the PCM stream via optical, digital coaxial and I2S HDMI or the DSD stream via I2S HDMI. This is the such product: HDMI/MHL To I2S IIS HDMI IIS I2S Dual-Mode Digital Audio I2S/Optical/DSD/Coaxial | eBay
  3. As you all may already know, there are no standards with I2S wiring via HDMI (nor for ethernet for that matter). So one would need to make sure that the I2S HDMI wiring of the source and the DAC matches to ensure that it works.
  4. I contacted the seller of said product from bullet point (2) and the seller provided me the I2S HDMI wiring diagram. As it is turns out, it is not compatible with my LKS MH-DA004 DAC. As such, I plan to build my own HDMI cable (using a solderless HDMI adaptor in the picture below) to match up the pins.
The help I am asking for is: Can someone (maybe an practicing electrical engineer) confirm for me that my diagram below will work and is safe? Please note that "NC" means, no connection, that the pin is not used. Also, it would be great if someone can explain the difference between ground and no connection in I2S HDMI.

Thank you all in advance for your help, much appreciate it.

Been there and done that.
I ended up with a DoP capable De embedder which works perfectly.

Check it out.......... https://www.ebay.com/itm/353354399159?
 
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UCrazyKid

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I bought one of those black boxes from China and didn't have any luck with it using my Oppo BDP-83 and Topping D90. YMMV
Now it collects dust.
 
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