Gefen Universal USB Audio Adpater
ADA-IMIC
The Gefen ADA-IMIC is a universal audio adapter which is a USB device that adds stereo input and output to your Mac or PC. With the iMic you can connect virtually any microphone or sound input device to your iBook, PowerBook, PowerMac or other Mac or PC with a USB port. The iMic audio adapter supports both Mic level and line level input. It also supports line level output for connecting speakers or an external recording device.
iMic's audio is superior to your computer's built-in soundcard because it uses USB for the audio signal. USB isolates the audio signal from the noisy electronics in your computer, giving you higher-quality sound when you record and higher-quality sound for external speakers.