BT601 is a way of encoding a signal, and not related to whether something is SD or HD. 720p is HD, by definition.

4:4:4 is chroma resolution, not colour space. Both signals that I showed the diagnostics for are 4:4:4, but it only specifies it for YCbCr since RGB is inherently 4:4:4.
As a christmas gift to myself I implemented the BMD chain to get mutlichannel SPDIF out of HDMI to feed my old Denon 5803A.
BMD Mini HDMI to SDI --> BMD SDI to Audio --> Neutrik NADITBNC (+ 12db T-pad)
HDCP is no issue for me, if it was I would get something like this: HDCP stripper
The Jitter measurement is the AES signal without pulse transformer.
Caution!: Center and LFE channel on the SDI standard seem to be swapped


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Over the christmas holidays I´ve tested the setup extensively and I am quite impressed by it. It even does sound "better" than SPDIF from my RME DAC on DTS core material. It sounded better with the ground connected through on the pulse transformer. To swap the center and LFE channel I use the Jriver player and ASIO4all output embedded in KODI. So don´t let those lovely AVR5803, AVC1 SRA go to waste - upgrade them!
Indeed - the used price seems affordable on those. Although the output seems to be encrypted?
"These four phono sockets each carry a pair of digital audio channel signals at up to 96kHz sample rate: 1/2, 3/4, 5/6 and 7/8. These are encrypted to Meridian High Resolution (MHR) specifications when carrying high resolution data."


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well, I am living proof, that this works.
You have to disable mmhr (and not transport high resolution data -> 44.1/48KHz only) via the Meridian Control Software and voila.

I used it with a Dolby CP650 and Dolby CP950 Cinema Processors via the (in Cinema Industrie) Standard CAT5 cable 8channel AES Connection.
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@yulen Can you explain how you did it?
The HDMI loop-out uses a chip that distributes two HDMI channels, one of which is used for the audio separation chip, and the other HDMI loop-out. The audio separation chip will convert the audio signals of the HDMI protocol into 4 sets of I2S signal outputs. Then the I2S signal is converted into an AES/EBU signal and output through the interface chip. This DIY box is mainly used for CP750 and CP650. The box comes with a remote control for CP750 and CP650, which can control the volume, channel selection and mute.
@yulen That all makes sense but can you provide anymore information on how to do it? Like what chip, where to get it? Links would be ideal.
I am trying to 5.1 audio from an appleTv into my studio audio processing system. I have 8 AES/EBU spare inputs.
For a box like Apple TV that can only output LPCM, it is most convenient to directly de-embed the audio signal and use it directly. There are many such de-embedding chips. I use ADI's ADV7612. You can search the data manual by yourself. ADI also has other HDMI multiple input and multiple output chips. Most of them are 8-channel 4 sets of I2S outputs. Converting I2S to AES is very simple and there are many chip solutions. Of course, you can also buy it directly from me. The unit price is US$180. The box comes with one HDMI input, one HDMI output and 4 sets of AES outputs with DB25 interface.
How did you split the HDMI signal?
I've used the HDMI to SDI and the SDI to Audio adapters from Blackmagic. But those do not work with copyrighted material and would require an additional hdcp stripper.
Edit: The SDI standard also has the Center and LFE channel flipped compared to HDMI - probably to make this conversion more of a pain in the ***. As all my material is not copyrighted and coming from a PC I can work around all of this.

The Meridian HD621 mentioned earlier seems like a good option as it can be purchased really cheap used and for 180$ Yulen's box too as my setup costs around double that.


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