How to set up Audacity

Setting Up Audacity

Go to the of (Devices tab in current Audacity Beta) and set both the playback and recording devices explicitly to your inbuilt sound device or other sound device your cable is plugged into. Do NOT select "Microsoft SoundMapper" on Windows machines.

If you want to record in stereo, change the recording channels on the same Audio I/O tab to "2 (stereo)" (this is in the Recording tab in current Audacity Beta)

Choose the line-in input source for the selected audio device:

Windows Vista or 7, choose the line-in option for the recording device you want to use (e.g. "Line-In: Realtek HD Device") in the "Recording Device" dropdown in the Audio I/O tab of Audacity Preferences (Devices tab in current Audacity Beta)
Windows XP or earlier or Linux, select line-in in Audacity's Mixer Toolbar input selector
OS X, the Mixer Toolbar will usually be greyed out on "default source". This is normal, but you must go to Apple Audio-Midi Setup (on OS X 10.2 or later) or System Preferences > Sound (pre – OS X 10.2), choose the sound device you are using and make line-in to be the source for the "Audio Input". Note: In Audacity Beta you may be able to choose line-in in the Mixer Toolbar without going into Audio MIDI Setup, if you have selected Built-In Audio in Audacity Preferences at Step 1. In case of difficulty, or if you have a USB or Firewire recording device, you must set the input in Apple Audio MIDI Setup.

If you cannot choose your input source as described above, or if the line-in input won't record, see our further help for your particular operating system at Mixer Toolbar Issues in the Audacity Wiki.

Monitoring

Decide if you want to "monitor" your recording, that is, hear it played back as you make it:

Windows or Linux: Try "hardware playthrough". To use this, open the system sound mixer e.g. Sound or Sounds and Audio Devices in the Control Panel of Windows Vista/7 or XP respectively, open the Playback section, then unmute line-in and turn the volume up.
OS X: Try "hardware playthrough" in the Audio I/O tab of Audacity Preferences (Recording tab in Audacity Beta).

If hardware playthrough does not work, or if the playback and recording devices in Preferences are different, choose "software playthrough" in the Audio I/O tab of Audacity Preferences (Recording tab in Audacity Beta). It neither playthrough works on OS X, obtain the free LineIn software playthrough tool. from Rogue Amoeba. Note: software playthrough will have a slight delay, and causes some extra load on the computer.

Set the volume level of your recording input. Click on the downward pointing arrow in the right hand (red) VU recording level meters:

and click "Monitor Input" ("Start Monitoring" in Audacity Beta). While playing a loud part of your tape or record, adjust the input level slider on the Mixer Toolbar so the recording meters are almost reaching the right-hand end of the scale. Don't let the meter bars actually reach the right edge, or the red hold lights to right of the meter will come on, indicating you'll have distortion in the recording. If the recording level meters are not visible, go to the of and check (click View > Toolbars > Show Meter Toolbar in Audacity Beta).