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Any Clock Sync Issue for using RME ADI-2/4 Pro SE as crossover ?

I think "clocking issue" will occur for using 2 USB DAC, as both DACs are working asynchronously.

But for AES/coaxial/Toslink connection, I'm not sure.
In my design, AES source signal will be input to the RME ADI ADI 24 SE.
After DSP, AES output goes into DAC 1.
Coaxial/Toslink output goes into DAC 2, or XLR to subwoofer.

There should be only 1 clock working as master (I think).
I have asked ChatGPT for more information, wishing anyone here can justify it:

"I connect the aes output of Matrix Audio X-SPDIF3 to the AES input of RME ADI-2/4 Pro SE for digital signal processing.After DSP, the AES output of RME ADI-2/4 Pro SE is connected to DAC 1 and Coaxial/Toslink output to DAC 2 for audio.Is there clock sync issue between them ?Which device act as a mater clock ?"

GPT answers:

" In your setup, the RME ADI-2/4 Pro SE is the central device for signal processing and will likely act as the master clock for both downstream DACs. Here’s how the clocking works in your configuration:

Clock Sync Between Matrix Audio X-SPDIF3 and RME ADI-2/4 Pro SE:

The RME ADI-2/4 Pro SE is likely using the clock embedded in the AES signal from the X-SPDIF3 as its reference. Alternatively, you can configure the RME to use its internal clock and allow it to reclock the incoming AES signal for better jitter performance.
Clock Sync Between RME ADI-2/4 Pro SE and the DACs:

The AES output to DAC 1 and the Coaxial/Toslink output to DAC 2 will carry the audio signal along with the clock derived from the RME ADI-2/4 Pro SE. Both DACs will sync to the clock in the incoming signal.
Potential Issues:
Clock Mismatch: If the DACs are unable to lock to the clock in their respective input signals, you might experience clicks, pops, or distortions. This is rare with high-quality DACs.
Jitter: Each additional step in the signal chain can introduce jitter, which could potentially degrade audio quality. However, modern equipment like the RME ADI-2/4 Pro SE and high-end DACs usually handle this well.
Recommendations:
Master Clock Configuration: Let the RME ADI-2/4 Pro SE serve as the master clock by using its internal clock as the reference. This ensures that all downstream signals are based on a single, stable clock.
Sync Settings: Check the sync settings on all devices to ensure they are configured to accept an external clock (in the case of the DACs) or to use the internal clock (for the RME ADI-2/4 Pro SE, if preferred)."
It seems the clocks of each device is working synchronously for AES/Coaxial/Toslink connection.
All sync to the RME's SteadyClock FS

What need to concern is only the phase adujustment of the subwoofer as an ordinary .1/.2 setup.
Hope I am correct.
 
More explanation from ChatGPT:

"RME’s SteadyClock FS is actively working in your setup and plays a critical role in maintaining clock stability and reducing jitter. Let me explain in detail how SteadyClock FS operates in your configuration and why it is beneficial.

What is SteadyClock FS?
SteadyClock FS (Frequency Synthesizer) is RME's advanced clocking technology designed to:

Stabilize incoming digital audio signals: It ensures the integrity of audio signals even if the external clock source has jitter or instability.
Minimize jitter: It reduces timing inaccuracies in the clock signal, which can degrade audio quality.
Flexibly adapt clocking: It allows the device to sync with external clocks or operate on its own high-quality internal clock.
How SteadyClock FS Works in Your Setup
1. Clocking from the Matrix Audio X-SPDIF3 to the RME ADI-2/4 Pro SE
Incoming Clock: The AES signal from the Matrix Audio X-SPDIF3 carries an embedded clock.
SteadyClock FS’s Role: When the RME ADI-2/4 Pro SE receives this AES signal, it extracts the clock. If the clock from the X-SPDIF3 has any jitter, SteadyClock FS stabilizes and reclocks the signal to ensure low jitter before further processing.
Internal Clock Option: If you configure the RME ADI-2/4 Pro SE to use its internal clock, SteadyClock FS will replace the incoming clock entirely with the high-quality internal reference clock, providing even better timing accuracy.
2. Clocking from the RME ADI-2/4 Pro SE to DAC 1 (AES) and DAC 2 (Coaxial/Toslink)
Output Clock: The RME sends digital audio signals to DAC 1 and DAC 2, embedding its own clock into the AES and Coaxial/Toslink outputs.
SteadyClock FS’s Role:
If the RME is using its internal clock, it ensures the outgoing clock is highly stable and low-jitter.
If the RME is syncing to the X-SPDIF3, SteadyClock FS ensures that the reclocked and stabilized version of the X-SPDIF3’s clock is transmitted to the DACs.
3. DAC Sync
Both DACs (DAC 1 and DAC 2) are configured to lock to the incoming signal's clock (embedded in the AES and Coaxial/Toslink streams).
The SteadyClock FS ensures that these clocks are stable, minimizing potential synchronization issues and jitter in the downstream DACs.
Key Benefits of SteadyClock FS in Your Setup
Reduced Jitter:

Jitter from the Matrix Audio X-SPDIF3 is corrected.
The outgoing signals to DAC 1 and DAC 2 are stabilized with minimal jitter.
Improved Audio Quality:

By providing a clean and stable clock, SteadyClock FS ensures the DACs receive precise timing, leading to optimal audio reproduction.
Flexible Clock Source:

The RME ADI-2/4 Pro SE can either sync to the external AES clock (from the X-SPDIF3) or use its internal clock. SteadyClock FS ensures stability in both cases.
Compatibility:

Even if the clock from the X-SPDIF3 is not perfect, SteadyClock FS ensures that the RME ADI-2/4 Pro SE and connected DACs operate without audible issues.
Practical Considerations
Recommended Configuration: Let the RME ADI-2/4 Pro SE use its internal clock as the master clock, ensuring maximum performance of SteadyClock FS.
Monitor Sync Status: The RME ADI-2/4 Pro SE provides indicators for clock sync and lock status. Check these in the device’s menu to confirm stable operation.
DAC Compatibility: Ensure both DAC 1 and DAC 2 are set to accept an external clock from their respective digital inputs."
 
I have looked into the user manual of the RME ADI 24 pro se, there is a multi-channel mode, for which my design is based on.
I suppose i can get better result compared to minidsp SHD's solution besides shortening the cable length of the audio path.
It helps if anyone can justify this setup.

Screenshot 2024-12-30 113814 - Copy.png
 
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How is your project going along?
 
if you are planning to use a PC for crossover or room correction, you could have PC -> Rme via usb, and have the 4 line outputs for subs +L/R directly out of the Rme adi 2/4
This setup also works as stereo preamp, using the 2 RME inputs to digitize the signal and the apply room correction. I use something similar.
 
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