USB or Optical Out To DAC

[holsen]

I'm brand new here and I'm so thankful to have discovered WiiM and Roon. I just picked up a WiiM Ultra to replace 2 pieces of Sonos Gear a Beam (For HDMI IN) and a Port to get into my B&O. Just a quick question. My external DAC will take Optical and USB input. Is there a concensus on which is the better way out of the Ultra?

 

[adias]

If your DAC has a good USB input and precision clocks, use USB.

 

[pieterv1]

I'm brand new here and I'm so thankful to have discovered WiiM and Roon. I just picked up a WiiM Ultra to replace 2 pieces of Sonos Gear a Beam (For HDMI IN) and a Port to get into my B&O. Just a quick question. My external DAC will take Optical and USB input. Is there a concensus on which is the better way out of the Ultra?

USB will allow the DAC to entirely rely on its internal clock and would be the preferred method. It's an asynchronous audio connection.

With toslink/coax, you have a higher chance of jitter and digital noise, although it's probably negligible with modern transports & DAC's. The transport and the DAC have to be in sync with eachother to properly read the digital audio.

The additional benefit of optical is that both devices will be galvanically isolated. There is no direct electrical connection between both devices as you're dealing with a light signal. This reduces the risk of possible ground loops in specific setups.