SPDIF out interface

[phe78]

Hi folks,
The TX816 has been a Graal for me when I was a teenager… imagine how I reacted when I realized I could get the equivalent with a raspi and other stuff for cheap … WARM thanks to you guys who managed to not only develop this but also make it approachable with clear instructions for me to make it work !!
Now my question : my studio is running out of analog inputs but still has SPDIF coax and optical ins available. Hence I’d like to add SPDIF outs to my raspberry. I saw some I2S boards such as this one : https://www.amazon.fr/dp/B07DK5C4TY?ref_=cm_sw_r_cp_ud_dp_WDVNDFCBMYAQQSEFPQ6X
Would that work with MiniDexed ? Also' would that work if connected with a PCM5122 analog out board at the same time ?
many thanks in advance for your feedback
Philippe

[probonopd]

Welcome @phe78. I don't think you can attach more than one i2s device at a time.

That board uses a WM8804G DAC. We are not listing this one as compatible at the moment. I doubt that S/PDIF would work without software changes anyway, because as I understand the data for S/PDIF is not generated from the i2s signal which we are using (not 100% sure on this one). So no, I don't think this will work currently. For professional use S/PDIF should probably be avoided due to jitter anyway and i2s should be preferred.

[sou7611]

Can a USB audio output be driven? If so, that might be an access for a digital audio signal (which could then be converted to AES or SPDIF)

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On Fri, May 13, 2022 at 1:44 PM probonopd ***@***.***> wrote: Welcome @phe78 <https://github.com/phe78>. I don't think you can attach more than one i2s device at a time. That board uses a WM8804G DAC. We are not listing this one as compatible at the moment. I doubt that S/PDIF would work without software changes anyway, because as I understand the data for S/PDIF is not generated from the i2s signal which we are using. So no, I don't think this will work currently. For professional use S/PDIF should probably be avoided due to jitter anyway and i2s should be preferred. — Reply to this email directly, view it on GitHub <#218 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ABNBVNBVT4LUVWG5QVZF3RTVJ2IIDANCNFSM5VZNMA2A> . You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>

[probonopd]

Don't professionals avoid S/PDIF?

[luisfcorreia]

not really, there are digital tribes

I for example, use ADAT to connect my two audio cards :)

[luisfcorreia]

USB Audio is not supported
(at the moment, at least)

[sou7611]

Well, then I'd look at it this way : none of the Yamaha gear supported digital outputs. Heck, not all of 'em even supported balanced outputs.

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On Fri, May 13, 2022 at 4:46 PM Luis Correia ***@***.***> wrote: USB Audio is not supported (at the moment, at least) — Reply to this email directly, view it on GitHub <#218 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ABNBVNGKOZOWDW2PGS6H763VJ25SHANCNFSM5VZNMA2A> . You are receiving this because you commented.Message ID: ***@***.***>

[sou7611]

SPDIF is fine as long as you have a free running clock, it's essentially the same thing as stereo AES. Where people get in trouble is when you need synced clocks, because SPDIF can't do that (but AES can) I've seen and used both formats, and many digital devices (mixers, interfaces, recorders, etc) can interface with both as well. SPDIF does have the advantage of optical connections, if you want to go that route.

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On Fri, May 13, 2022, 5:17 PM probonopd ***@***.***> wrote: Don't professionals avoid S/PDIF? — Reply to this email directly, view it on GitHub <#218 (reply in thread)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ABNBVNHP7PJQTSXFHONAQTLVJ3BFPANCNFSM5VZNMA2A> . You are receiving this because you commented.Message ID: ***@***.***>

[sou7611]

Something else to consider as a way to extract a digital audio stream... Use a HDMI audio extractor to extract the digital audio, e.g. an HDMI audio de embedder.

There are several inexpensive models on Amazon that output SPDIF in addition to analog audio.

[probonopd]

Yes, that should work.

[phe78]

Many thanks to you all for your great replies ! I didn't think about the HDMI audio extractor, thats a great idea. So for the time being I'll go with my 5122 DAC board. I just made a test with breadboard connections, worked great right away. Now build a board with plugs connecting the display encoder and GPIOs. Will keep you folks posted !