Connect Gustard U12 direct to DAC Board

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Guys

Love the site there is some much here that I do not understand.

I am hoping you can explain to a simple man if this is possible and if not what I need to do.

Goal get a new DAC.

I saw this and thought good - HiFi parallel PCM1794A decoder board DAC core board 24Bit 192kHz V2.0 version

HiFi parallel PCM1794A decoder board DAC core board 24Bit 192kHz V2.0 version | eBay

I have a Gustard U12

Gustard U12 USB DAC DSD 0.1PPM 384KHz 32BIT Digital Audio Interface Black XMOS | eBay

My simple question is:

Can I connect the output of the Gustard U12 (I2S) to the input of the above board?

If yes, can I get a HDMI to the 5-pins on the board

If not, what do I need?

I like this board (suggestions welcome) as my complete system is BALANCED. Yes, it has ALL XLR.

D
 
The HDMI I2S will be sent in LVDS (differential signalling) whereas the 1794 board has normal I2S as its input. You will need an LVDS receiver chip (4 channels) to convert from one to the other. You'll also need to verify that the transmitted MCLK frequency is the right one for the 1794s as its not part of the I2S spec.


Here's an example of a board which will handle the interface for you : Module d'entree HDMI I2S LVDS vers Sortie I2S | eBay
 
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Sir

You are very smart. Thank you. I am in the Australian Bush, so no resources here.

1. Module d'entree HDMI I2S LVDS vers Sortie I2S | eBay

Looks great – thank you.

For my continued education:

you saying - that all I2S signals sent via HDMI are LVDS and the PCM1794A board only receives normal I2S. or its it specific to the Gustard U12?

Here I am showing my total ignorance:

How would I verify that the transmitted MCLK frequency is the right one for the 1794s or do you mean the PCM1794A board?

2. Board - I did find this board also on eBay - IIS / I2S Long Range Transmission Interface by HDMI (Input and Output Modules) | eBay

that also appears on Audiophonics - Interface module HDMI input to I2S

3. Board - Plus also on Audiophonics a far more complex board - I2S LVDS HDMI to I2S / SPDIF Digital Interface - Audiophonics
As I am a total idiot….

· I need to confirm that the transmitted MCLK frequency is the right one for the PCM1794A board – no idea how
· Board #2 or # 3 would be OK (easier for me as there is no soldering), with some pins spare – (except on board 3 as board #2 looks like a cutdown version???)

Is my understanding close to reality?

I am going to regret this: but with board #3 there are extra pins: PCM/DSD and SPDIF: I am assuming that since I am using the I2S output of the Gustard the SPDIF is irrelevant as it is not transmitted, but what about PCM/DSD or does this come with LDVS/I2S??

Please excuse my ignorance.

Thank you
D
 
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The transport of I2S over HDMI connectors (note its only the connectors and cabling being used which are HDMI, not the protocol) isn't an industry standard. More an audiophile niche thing so it would be sensible to check that the allocation of pins to logical function is the same at both ends.

I checked the datasheet for PCM1794A and found it can handle most ratios of MCLK (128* up to 384*) to sample rate so perhaps that's not going to be a problem in this instance.

Your first link (2.) is to a pair of boards - the receiver board is the one you need, you'll have no need for the transmitter. The second (Audiophonics) board looks fine too, a little simpler than the one I found on eBay. The (3.) board is more complex as it has an S/PDIF transmitter too. If you had an S/PDIF receiver already then the S/PDIF output of the Gustard would be the one to use, its more plug-and-play than I2S over HDMI.


As regards DSD, I have no experience at all so hesitate to comment.
 
Sir

Once again – thank you.

You have made my day – thank you again.

I have much higher aspirations than my abilities.

I think I will keep it simple. Board #2 from eBay. Thank you for pointing out there are 2 board (they look almost the same). They got me with the 2 boards, but same price as Audiophonics for 1 and I noted it was not available.

Lucky. Thank you.

Must be exciting for a Brit to be living in Hangzhou.

I will order and then move on to the next challenge of the build

Regards
D
 
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