No announcement yet.

Capture card necessary to use Optical In?

  • Filter
  • Time
  • Show
Clear All
new posts

  • Capture card necessary to use Optical In?

    I'm trying to capture a live 6-channel input through the Optical Audio In on the back of my Mac Pro. I want to capture all 6 channels simultaneously. I'm using a digital optical cable. The source is a DVD audio disk, so it's not possible to extract the audio files from the disk (as far as I know). I'm going into Log and Capture and selecting Non-Controllable Device and Generic Capture Template, and choosing 6 channels. My System Preferences have the Optical In selected as the input.

    The preview tends to give me a snapshot of the first channel, but it sticks and doesn't change. Clicking Capture Now does nothing. The system doesn't seem to recognize that 6 channels are coming in. Do I need to have a capture card to make use of this input? Does it have any function out of the box?
    Mac Pro 3.0 Ghz, OS 10.5.6, 5 GB RAM, FCP 5.1.4, QT 7.6, ATI Radeon X1900

  • #2
    Optical inputs are a stereo, 2 channel input. I've never known only two optical audio ports to carry more than 2 channels of audio. You're only routing one channel of a stereo pair, which is why your "snapshot" is sticking. Those optical ports are just like a copper stereo pair, just optical, to avoid the degradation of copper wires.

    You can use several pieces of software to extract the audio from the DVD.
    Are you trying to capture the surround sound?

    You're going to need something like a ProSonus Firestudio to get each channel separately, "after" coming out of a DVD player's surround sound speaker outputs, all 6 of them.
    Digital Media Instructor for
    Louisiana State University & Delgado College