Multi-channel ADC with HDMI output?

[rah]

1. Connect your eight analog audio channels to four stereo ADCs (may be cheap or somewhat expensive). This will yield four SPDIF outputs.
2. Connect the four SPDIF outputs from your ADCs to a Blackmagic Audio to SDI Mini Converter. This will yield a single SDI output with the content of your eight analog input channels.

You can just chain two Blackmagic Audio to SDIs to get eight analogue inputs. And FYI, it's far from a given that any particular AES/EBU input will take coaxial S/PDIF.

 

[phofman]

I did not find anywhere if the signal to the 4 AES/EBU inputs for that converter must be synchronous. The device block diagram does not show any async resampling to fit one common clock.

 

[Weeb Labs]

You can just chain two Blackmagic Audio to SDIs to get eight analogue inputs. And FYI, it's far from a given that any particular AES/EBU input will take coaxial S/PDIF.

That would certainly work but would be more expensive than the cheap ADCs.

Regarding SPDIF compatibility, it is undocumented but does work and has been confirmed by various owners.

I did not find anywhere if the signal to the 4 AES/EBU inputs for that converter must be synchronous. The device block diagram does not show any async resampling to fit one common clock.

There are defeatable SRCs on each of the inputs.

 

[phofman]

There are defeatable SRCs on each of the inputs.

Thanks but that description does not say what happens when all 4 inputs run at 48kHz, but all of them run asynchronously (which would be the case if 4 individual ADC -> SPDIF boards were used for the conversion)

 

[rah]

That would certainly work but would be more expensive than the cheap ADCs.

The "cheap" device you linked to is a DAC and not an ADC. Four of the "somewhat expensive" ADCs you linked to would be much more than one Blackmagic ADC.

Regarding SPDIF compatibility, it is undocumented but does work and has been confirmed by various owners.

To be clear, I meant in general, not just on this device.

 

[Weeb Labs]

Thanks but that description does not say what happens when all 4 inputs run at 48kHz, but all of them run asynchronously (which would be the case if 4 individual ADC -> SPDIF boards were used for the conversion)

The purpose of the SRC is to resample the input to the SDI clock. Whether they are a mixture of 44.1KHz and 48KHz or just the latter and asynchronous (different but much closer sample rates), the SRC’s task is the same if enabled.

The "cheap" device you linked to is a DAC and not an ADC. Four of the "somewhat expensive" ADCs you linked to would be much more than one Blackmagic ADC.



To be clear, I meant in general, not just on this device.

It appears that I embedded the wrong link but can no longer edit it. This is the one which should have been embedded.

 

[rah]

Thanks but that description does not say what happens when all 4 inputs run at 48kHz, but all of them run asynchronously (which would be the case if 4 individual ADC -> SPDIF boards were used for the conversion)

The shop page description says this:

"On modes with AES/EBU digital audio in, a sample rate converter lets you connect to any AES/EBU source, either synchronized, or un-syncronised."

So it looks like it does support AES/EBU inputs running asynchronously.

 

[BILLMICH88888]

does anyone know of any AVR's that would take the analog multichannel input, run it through it's ADC, then send that audio out via HDMI?

 

[phofman]

does anyone know of any AVR's that would take the analog multichannel input, run it through it's ADC, then send that audio out via HDMI?

Please read the previous pages of this thread, it was already discussed here.

 

[BILLMICH88888]

I did read them, closest I saw was Marantz could do it, but only with 2 channel output (no bueno for me)
never discussed that NO OTHER AVR could do it........

 

[Weeb Labs]

I did read them, closest I saw was Marantz could do it, but only with 2 channel output (no bueno for me)
never discussed that NO OTHER AVR could do it........

Almost all conventional AVRs make use of a very similar signal chain. To my knowledge, there are none which feed the multichannel analog inputs through ADCs. Alternative solutions were presented here and here.

 

[BILLMICH88888]

thank you very much ... appreciate you taking the time to respond

 

[ace_xp2]

The old harman 645 and 7550 avrs used to put the multi channel through the adc. At least I would think it would have to, as the multi channel inputs had full crossover control (the only time I've come across that). That being said, I've no idea if the signal went back out anything but the analog outs.

 

[MCH]

Far from what OP asked, but if someone is interested, there might be information enough available to DIY a 8 channel to hdmi interface with the old ITE IT66121 hdmi transmitter:
It is possible to buy a board with the necessary supplies and connectors and a header exposing the input pins that I cannot find right now but I think it costs something like 15$. The people that sell the board provide a driver, unfortunately only for stereo audio, but there is a programming guide here:

https://rockchip.fr/radxa/IT66121_Programming_Guide.v1.05.pdf

 

[JediJoker]

does anyone know of any AVR's that would take the analog multichannel input, run it through it's ADC, then send that audio out via HDMI?

Only TOTL, prosumer/professional gear from the likes of Trinnov.

 

[phofman]

IMO this requirement (unless very low latency were required) could be solved quite simply, no need for any expensive proprietary HW. This project already shows ADC8x with CamillaDSP on RPi5 https://audiosciencereview.com/forum/index.php?threads/rpi-camilladsp-tutorial.29656/post-2264232 . Just reconfigure CDSP to output to the RPi's HDMI 8ch audio device instead + enable rate adjustment via async resampler in CDSP and the core feature is done. In addition you get a very powerful DSP with web UI.

 

[BILLMICH88888]

Only TOTL, prosumer/professional gear from the likes of Trinnov.

thank you for the response, what is TOTL - what does it stand for?

 

[welwynnick]

thank you for the response, what is TOTL?

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