1 Topic by mavck (edited by mavck 2022-04-04 08:45:46)

  • mavck
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Topic: 2 technical questions (PRO)

Hi, all.
I have two questions. One is about SRC itself and the other one about the behavior of the unit.

1) When I use SRC with the Optical input, and I use it for ADAT by the way, it takes in the audio as 2 channels when the signal is in 96kHz, and it takes it as 1 channel when it is in 48kHz (not the case without SRC).

If I use the same source device, but with S/PDIF Coaxial, no such thing happens, and SRC On or Off result in only 1 channel, regardless of the sampling rate.

Why does this happen? Is this correct?


2) I think might actually be a technical issue, please let me know.
Every time I switch modes (Basic mode), and get to DAC mode, it always, always changes my SPDIF settings from Optical to Coax.
I just checked and going to the Optical/Coax setting when in DAC mode, this is grayed out... What is the reason for this?
It does 2 additional things: 1- it turns SRC off and 2-It changes the clock source to SPDIF (the clock thing I can understand, but still).


Thanks to anyone willing to help. I am rather to to this world of fancy digital audio stuff, and while I have learned a lot thanks to my ADI, there is still plenty to learn.

  • KaiS
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Re: 2 technical questions (PRO)

Changing the “Mode” loads a factory default parameter set.

Store and recall a “Setup” for each configuration you want to use.
A Setup stores the whole configuration of the device.

The Setups can be assigned to a button on the remote or front panel for easy access.

The button assignment is stored within the individual Setup too, not globally.
This can be used to toggle through numerous Setups with a single button, like e.g.:
Button X press recalls:
- Setup2 when in Setup1
- Setup3 when in Setup2
- Setup1 when in Setup3

KaiS's Website

3 Reply by MC

  • MC
  • MC
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Re: 2 technical questions (PRO)

mavck wrote:

When I use SRC with the Optical input, and I use it for ADAT by the way, it takes in the audio as 2 channels when the signal is in 96kHz, and it takes it as 1 channel when it is in 48kHz (not the case without SRC).

Manual chapter 22.3: ADAT has an issue in that its sample rate range (single, double, quad speed, or default, SMUX2, SMUX4) is often not signalled, sometimes even incorrectly. Therefore the user usually has to set the sample rate manually to the correct range, especially when the unit is in clock mode slave, so that demuxing works correctly.

Using the SRC on ADAT might break that logic, when you run the SRC in 96 kHz but apply 48 kHz ADAT. In that case I don't see a way to handle this correctly, but will check it myself (tomorrow).

Regards
Matthias Carstens
RME

MC's Website

4 Reply by mavck (edited by mavck 2022-04-04 16:01:57)

  • mavck
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Re: 2 technical questions (PRO)

MC wrote:
mavck wrote:

When I use SRC with the Optical input, and I use it for ADAT by the way, it takes in the audio as 2 channels when the signal is in 96kHz, and it takes it as 1 channel when it is in 48kHz (not the case without SRC).

Manual chapter 22.3: ADAT has an issue in that its sample rate range (single, double, quad speed, or default, SMUX2, SMUX4) is often not signalled, sometimes even incorrectly. Therefore the user usually has to set the sample rate manually to the correct range, especially when the unit is in clock mode slave, so that demuxing works correctly.

Using the SRC on ADAT might break that logic, when you run the SRC in 96 kHz but apply 48 kHz ADAT. In that case I don't see a way to handle this correctly, but will check it myself (tomorrow).

Hi, MC.
Thank you for your answer.
I thought this might come up, I should have mentioned that I am using the ADI as a master all the time, and the slave audio interface is set to ADATx2 for clock source.
Please note this issue only happens with SRC, never without it. And I am setting all things to the same 96kHz clock too, manually.
The only difference is SRC or no SRC in ADAT. No SRC, my mono signal comes in in one channel. SRC and my mono signal becomes 2 channels.

BTW, I have no way to test S/PDIF via Toslink, so my S/PDIF testing is done via Coax, and my ADAT via Toslink.

I'll be waiting for your test results!

5 Reply by MC

  • MC
  • MC
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Re: 2 technical questions (PRO)

I tested the ADAT SRC functionalityand it works as expected, at single and double speed. It can decouple clock and convert from single to double and double to single correctly, with ADAT input signal.

To keep this short: Go to the State Overview display and check what sample rate the ADI sees at 44/48/ or 96 kHz. I tested with the Babyface, which signals the double speed rates correctly. With that information missing ADAT double speed operation will not work correctly.

Regards
Matthias Carstens
RME

MC's Website