Choosing a Line-In or Internal Mic for GarageBand in iLife ’11

By Tony Bove from iLife '11 For Dummies

When using GarageBand in iLife '11 you can connect any type of mono or stereo audio source. Most Mac models offer a line-in connection that accepts a cable with a 1/8-inch stereo mini-plug, which is common in many music-lover households. Thanks to GarageBand in iLife '11 you can connect audio sources such as a CD or DVD player, an electric instrument, an electric guitar, a mono microphone or even a stereo set of microphones.

Here’s how the connections work:

For home stereo gear, all you need to do is find a line-out connection on your stereo system (for line-level output) and connect to it a cable that uses RCA-type left and right (typically marked white and red) stereo plugs or a stereo mini-plug. If you use RCA-type plugs, use an RCA-to-stereo-mini-plug converter or a cable that offers a stereo mini-plug on the other end.
For electric instruments such as guitars and microphones, you can use a phono-to-mini-plug converter such as the Monster Instrument Adapter. It's a short cable that has a mono 1/4-inch phono connection on one end and a 1/8-inch mini-plug on the other end to connect to your Mac’s line-in connection.

However, the sound quality isn’t at its highest level — an electric guitar or microphone produces a low input signal, resulting in low volume when you record. You want a line-level source of audio — either line-level output from your instrument, your microphone, your amplifier, preamp or via an audio interface.

If your Mac doesn’t offer a line-in connection, you can purchase a USB audio input device, such as the Griffin iMic or the Roland UA-30, and use it with the Mac’s USB connection.

The Mac’s internal microphone can also be useful, especially when recording sound effects or ambient sound on the road with a laptop.

After connecting your gear, you need to assign sound input to your Mac’s line-in connection. If you’re using the internal microphone, make sure the sound input is assigned to it.