[arch-general] HDMI audio input - HDMI microphone

[Neven Sajko]

On Wed, 27 Feb 2019 at 19:58, Ralf Mardorf <silver.bullet at zoho.com> wrote:
>
> On Wed, 27 Feb 2019 19:07:51 +0000, Neven Sajko wrote:
> >> Prosumer, as well as professional audio interfaces work very good
> >> using the class compliance Linux USB driver. I own a prosumer audio
> >> interface with 18 input and 20 output channels and there are no
> >> issues using all of them and moreover, the prosumer USB device works
> >> way better, than my professional PCIe audio interface.
> >
> >Hmmm, one advantage of PCIe is that it provides 3.3 V which does not
> >have to be divided for supplying the microphone with it. Also PCIe
> >causes less latency, but that is not really important for my use case.
> >
> >But I do not really see why would USB be a bad choice...
>
> If you are using a single audio interface for recording and playback all
> your digital (ADAT, S/PDIF, AES/EBU) and analog equipment, you only need
> to handle a single audio interface via Linux or any other OS. This audio
> interface needs to sync (at best via word clock) to connected digital
> gear, too, but for the OS it's just one interface. While it's possible
> to use more than just one audio interface and it's also possible to
> sync several interfaces, it's an annoyance to use more than just one
> audio interface. You would end up making several synced audio interfaces
> a single virtual audio interface or use some resampling solution, if
> sync via hardware shouldn't be provided. In short, if you should use 4
> USB microphones, you would have to handle 4 audio interfaces, instead of
> one. Without a workaround you won't be able to use those for 4 audio
> interfaces for example with jackd. Workarounds steal time that could be
> better used.

Thank you for the insight!

Summa summarum: if the user needs to use more than one microphone
device (for recording separate sound sources), USB is a bad choice for
the microphone compared to ADAT, S/PDIF, or AES/EBU.

But in my case just the one microphone array is all that will run at
the same time, and I want it connected directly to my PC, so USB or
PCIe seem like the most natural interfaces.

Regards,
Nsajko