External Clock Connection Issue with RS130

#1

Subject: External Clock Connection Issue with RS130

Hello @Rosehan,

I hope you’re doing well. I’m using my RS130 with the Gaia DDC and Terminator Plus DAC. My goal is to synchronize these devices through an external clock connection, but I’m experiencing issues with getting the RS130 to work with the external clock signal. Below are the details.

Objective:

To synchronize the clocks of the RS130 and Terminator Plus through the Gaia DDC.

Connections:

  1. Gaia → RS130:

I connected the 45 MHz output from Gaia to the 75-ohm clock input on RS130 using a SoTM 75-ohm BNC cable.

I selected the 75-ohm external clock option in the RS130 menu.

  1. Gaia → Terminator Plus:

I connected the 49 MHz output from Gaia to the clock input of Terminator Plus using a second SoTM 75-ohm BNC cable.

I configured Gaia and activated Terminator’s clock inputs, and both devices worked perfectly.

  1. RS130 → Gaia (USB):

I connected RS130 to Gaia via a USB cable.

  1. Gaia → Terminator (I2S):

I connected Gaia to Terminator using an I2S cable.

Issue I’m Facing:

RS130 is not detecting the external clock signal from Gaia. Below are the steps I have taken to resolve the issue, but without success:

  1. Menu Settings:
    I selected the 75-ohm external clock option in RS130’s menu, but the device did not detect the external clock, and no sound was produced. However, when I switched to internal clock mode, the sound worked perfectly.

  2. Cable Direction:
    I checked the direction of the SoTM BNC cables between Gaia and RS130 to ensure they were connected correctly, but this did not solve the issue.

  3. Firmware Update:
    I updated the firmware of RS130 and also rolled it back to previous versions, but neither resolved the issue.

  4. Connection Paths:
    I reviewed the connections using both USB and I2S between Gaia and Terminator. While Gaia and Terminator work without issue, RS130 still does not detect the external clock signal.

Final Question:

I have read on some forums that other users have experienced similar issues with USB connections involving RS130. Specifically, there are reports that synchronization issues occur when using RS130 with devices like Gaia DDC over USB. Could this be impacting the external clock detection as well? Is there any hardware incompatibility between Gaia and RS130?

Any additional information you can provide would be greatly appreciated in resolving this issue.

Thank you for your help,
Oben Ünser

#2

Hello again,

When I researched the issue on your forum, I saw that it mentioned RS130 cannot work with clock signals other than 10 MHz. Since the clock signals sent from Gaia DDC are 45 MHz and 49 MHz, could this be the reason why RS130 is not able to detect the external clock?

In RS130’s menu, the internal oscillator is set to 10 MHz. Could this frequency mismatch between Gaia and RS130 be causing the issue with detecting the external clock signal? If so, what would you recommend as a solution?

Any information you can provide would be greatly appreciated.

Thank you,
Oben Ünser

#3

Yes that is the problem. The clocks have to send the same signals.

#4

… Which must be 10 MHz only !