Audio I/O Configuration Logic 8 Pro

Discussion in 'Recording Gear and Equipment [BG]' started by Davebass, Jun 22, 2008.

  1. I'm having playback issues on logic pro 8, im working on a standard leopard running mac. i use a USC audio codex (USB<->Phono) device to send and retrieve my audio signal. my problem is not receiving the audio its is sending it out back through my desk. i get lots of hiss on the way back out. i plugged my speakers into the headphone mini jack and was all fine. I'm now having trouble bringing the audio in through USB and out through headphone mini jack. Anybody have any ideas?


  2. Bump!
  3. lovenotfear


    Aug 15, 2007
    Las Vegas, NV
    do you have to many usb devices plugged into your ports on your mac? the less the better, also how are you running your latenzy settings? and what sampling rate are you recording at? if you set it to high i can give you problems if your equipment is not up to the task, more ram, etc...... i am trying to understand your exact issue, not to be rude, but what you are saying is all over the place, so i am trying my best to undersatnd your exact problem, what mac do you have, how much ram, how fast is the processor, what kind of sound card ,how many plugins are you running etc....:)
  4. im running a macbook with 2gb ram at 2.4 ghz. my USB inputs are a mouse and the desk input. the sample rate is at 44.1. i know my problem seems far out but that is my main reason for asking.

    the sound card is a small behringer desk with a phono to USB adaptor attached.

    ive narrowed it down to be that when i send a audio signal out of the mac through the USB it distorts. so basically what id like to know is if i can set a independent output on the software to bypass the USB output and go straight through the headphone output. so far i have had no look finding such an option and am wondering if it is actually possible.
  5. DocBop


    Feb 22, 2007
    Los Angeles, CA
    Go to the OS X System Preferences and click the Sound icon. Then selecto Output tab. There is where you select where to send the output. In Logic check your Preference too. Preferences Audio, Devices tab, Core Audio tab, Device drop down list select the built in port.

    Remember Preferences in Logic are global so whatever preferences you select will be for all projects. Setting are per project.
  6. Brent Nussey

    Brent Nussey

    Jun 27, 2001
    Tokyo, Japan
    Hi Dave.

    If you want to use your interface as an input and the built in output of the macbook *at the same time*, you'll have to create an Aggregate Device. This is a way of using multiple interfaces at once in Logic. It's detailed in the manual very well, but I won't do it here, because I don't think it's the best option for you. I couldn't find any information on the "USC audio codex" to try to figure out where the hiss is coming from, but based on what you wrote, I think this must be a cheap stereo USB converter. My guess is that the built in converters in the macbook are probably just as good. So set your USB to phono converter aside, pick up an RCA (phono) to 1/8" jack converter cable, and plug the output of the mixer into the line input of the Macbook. Set your preferences to line in, and you're good to go.

  7. your spot on about the cheap phono -> USB convertor brent. im going to try your phono -> mini jack idea asap. i may also give the aggregate device a shot aswell if im feeling adventurous! thanks a lot!