HDMI Audio to USB Conversion?

[linuxfan]

But it’s still interesting to find a diy solution for this.

Well it should be possible to install an LVDS/I2S interface board into an Okto DAC. This is what you need -
https://www.audiophonics.fr/en/diy-...ipi-receiver-hdmi-to-i2s-dsd-dop-p-13981.html
You would connect this board's I2S output connections to the I2S input of the Okto main DAC board, displacing the connection from the existing USB interface board.
But of course you might not wish to permanently disable the USB interface, so in this case you might wish to make the connections swappable via headers, or there's a digital data switch board available from Twisted Pear Audio -
http://www.twistedpearaudio.com/control/otto.aspx

It might be worth asking the Okto people for advice. An earlier release of the Okto DAC was a DIY module, so I think the Okto developers are open to custom requests.

 

[JoachimStrobel]

I received a private message asking about how to get multi-channel HDMI audio to an Okto Researc dac8 PRO. It's a good question. The Okto dac8 PRO is one of only a few commercially available 8 channel DAC's. The other two I'm aware of are the exaSound and Motu. All of these DAC's are intended to be used with USB input, which is fine if your source is computer, but not very useful if your source is a Blu-Ray player or streamer.

I don't have a simple answer, apart from some complicated DIY solutions, but long term it may be worth lobbying these companies to add a direct I2S input to their DAC's. Then an intermediate HDMI extractor device can be used, such as this -
https://www.audiophonics.fr/en/diy-...-hdmi-mhl-to-i2s-coaxial-optical-p-13419.html

Maybe someone else can jump in with a solution.

My understanding is, that the HDMI licensing only allows de-embedding of RedBook equivalent Audio: 2 Ch 44/16. We would have to wait for patent circumventing Chinese boxes to do more.
Otherwise it is something that well connected audiophiles should fight for with the industry. An HDMI to USB Mch 96/24 conversion would open the door to modular Mch concepts much more easily.

 

[linuxfan]

We would have to wait for patent circumventing Chinese boxes to do more.

Patent-circumventing Chinese boxes actually do more right now - including decryption of DSD-over-I2S !!! As I reported earlier in the 3rd post of this forum thread
https://www.audiosciencereview.com/...mi-audio-to-usb-conversion.11481/#post-329194

The board-only version is currently this -
https://www.ebay.com/itm/HDMI-MHL-I...er-HDMI-to-I2S-IIS-HDMI-OVER-I2S/324024089544

And the fully boxed version is this -
https://www.audiophonics.fr/en/diy-...-hdmi-mhl-to-i2s-coaxial-optical-p-13419.html

 

[JoachimStrobel]

Patent-circumventing Chinese boxes actually do more right now - including decryption of DSD-over-I2S !!! As I reported earlier in the 3rd post of this forum thread
https://www.audiosciencereview.com/...mi-audio-to-usb-conversion.11481/#post-329194

The board-only version is currently this -
https://www.ebay.com/itm/HDMI-MHL-I...er-HDMI-to-I2S-IIS-HDMI-OVER-I2S/324024089544

And the fully boxed version is this -
https://www.audiophonics.fr/en/diy-...-hdmi-mhl-to-i2s-coaxial-optical-p-13419.html

Does the box care for HDCP?

 

[linuxfan]

Apparently no. An additional feature of this device (like many/most other Chinese HDMI splitters) is that HDCP is effectively removed from the pass-through HDMI signal.
This is what I have been told by others. If you want to know for sure, you could consider asking forum member fabien32, who was involved in this discussion earlier, and has one of these boards.

 

[mga2009]

Apparently no. An additional feature of this device (like many/most other Chinese HDMI splitters) is that HDCP is effectively removed from the pass-through HDMI signal.
This is what I have been told by others. If you want to know for sure, you could consider asking forum member fabien32, who was involved in this discussion earlier, and has one of these boards.

Been following the thread for a while, trying to learn some of the basics...

Would this board allow to extract all 8 audio channels from an HDMI signal and convert it to I2S so you can feed it to a DAC?
https://www.aliexpress.com/item/4001176293588.html

I understand the audio from the HDMI should be in PCM and without copy protection, although the Analog Devices's website, says the ADV7513 can even decode HBR Audio.
https://www.analog.com/en/products/adv7513.html#product-overview

 

[Aerith Gainsborough]

Meeeh I wish there was an easy way to get multichannel HDMI audio into my PC in order to pipe it through Dirac Live.
As it stands right now, the only way to make it happen would be to brute force it via an 7.1 HDMI -> Analog extractor which then feeds into a multichannel USB audio interface.

Guess I am stuck watching 4K Blu-Ray on headphones ... or uncorrected speakers for the time being.

 

[Kal Rubinson]

Meeeh I wish there was an easy way to get multichannel HDMI audio into my PC in order to pipe it through Dirac Live.
As it stands right now, the only way to make it happen would be to brute force it via an 7.1 HDMI -> Analog extractor which then feeds into a multichannel USB audio interface.

I'd sooner investigate playing with a used Meridian H621 and feed the 4xAES3 outputs to an Okto DAC8 Pro or a miniDSP U-DIO8. There is also a possible option for AES-EBU.

 

[Aerith Gainsborough]

Interesting idea but honestly not very economical to implement.
Simplest option would be to grab a Denon 3700H (or it's successor when I am ready) and let Audyssey do the correction for movies while keeping Dirac Live as-is for music.

I doubt that I would notice much difference between the two correction applications while being distracted by HDR explosions on my screen.

 

[Beershaun]

Yep. The content creators and rights holders use HDMI for drm copy protection reasons and it's designed so people cant run their intellectual property through a pc or tape recorder and pirate their work. Thats why you don't see HDMI to usb.

 

[Maltman]

I'd sooner investigate playing with a used Meridian H621 and feed the 4xAES3 outputs to an Okto DAC8 Pro or a miniDSP U-DIO8. There is also a possible option for AES-EBU.

Kal, do you know if the same „hack“ is possible with the newer UHD722?

 

[Kal Rubinson]

Kal, do you know if the same „hack“ is possible with the newer UHD722?

I do not know but I suspect so. The lurking issue is being able to make default settings in the Meridian boxes.

 

[Maltman]

I do not know but I suspect so. The lurking issue is being able to make default settings in the Meridian boxes.

why? There’s some RS232 or USB port to code them.. do you know More?

 

[mga2009]

I do not know but I suspect so. The lurking issue is being able to make default settings in the Meridian boxes.

Kal,

Do you know if Meridian HD621 outputs AES/EBU thru MHR (SPDIF) or MMHR (RJ45)? I though this protocols where encrypted and only usable within Meridian equipment.

 

[Maltman]

Kal,

Do you know if Meridian HD621 outputs AES/EBU thru MHR (SPDIF) or MMHR (RJ45)? I though this protocols where encrypted and only usable within Meridian equipment.

The RJ45 is basically an AES/EBU Output. It’s only encrypted for highres Audio. 48khz is open. Theres a Thread at meridian unplugged with all details.

 

[Kal Rubinson]

why? There’s some RS232 or USB port to code them.. do you know More?

RS232.

 

[Kal Rubinson]

The RJ45 is basically an AES/EBU Output. It’s only encrypted for highres Audio. 48khz is open. Theres a Thread at meridian unplugged with all details.

Also, I posted some of the details here on ASR a while back.

 

[Maltman]

I do not know but I suspect so. The lurking issue is being able to make default settings in the Meridian boxes.

just catched one in mint condition for only 900€. I’ll find out soon

 

[Ozymandias]

Patent-circumventing Chinese boxes actually do more right now - including decryption of DSD-over-I2S !!! As I reported earlier in the 3rd post of this forum thread
https://www.audiosciencereview.com/...mi-audio-to-usb-conversion.11481/#post-329194

The board-only version is currently this -
https://www.ebay.com/itm/HDMI-MHL-I...er-HDMI-to-I2S-IIS-HDMI-OVER-I2S/324024089544

And the fully boxed version is this -
https://www.audiophonics.fr/en/diy-...-hdmi-mhl-to-i2s-coaxial-optical-p-13419.html

@linuxfan Does this use DoP when outputting DSD over the coax/optical outputs? Thanks

 

[ElNino]

This is a related question: does anyone know of any external boxes that decode and output HDMI CEC volume control instructions?

CEC lets you use your TV remote to send volume control messages to receivers. I'd like to intercept those messages in software to control the volume of a software-based solution.

If there isn't anything like this out there, does anyone know of external HDMI to S/PDIF (or USB) boxes that optionally apply CEC volume control to the outputted S/PDIF stream? i.e., multiply the digital output by the CEC volume control level and then output that via S/PDIF?