Posted 10 October 2008 - 07:43 PM
Line-in is an input (normally stereo) that accepts a signal level as would be supplied by an audio component such as a CD/MP3 player or tape deck, or a music keyboard, much higher than microphone level.
Whether it's available may depend on how your sound is configured - for example the mic and line in can share a single socket and you set which one is operative in the sound card's control applet. Other cards have an input socket for each and mic and line input can operate concurrently.
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