Choose iTunes > Preferences, click General, and click Import Settings.

Choose an encoding format from the Import Using pop-up menu.

• AAC Encoder: Use for most music. You can listen to songs encoded using this format in iTunes, on iPhone and iPad, and on iPod models that come with a dock connector.

• AIFF Encoder: Use if you want to burn high-quality CDs with the songs you’re importing without losing audio quality.

• Apple Lossless Encoder: Use if you want to listen to imported songs on audiophile-quality sound systems without losing audio quality. (Songs imported using this format take up much more disk space.)

• MP3 Encoder: Use if you plan to listen to music in apps other than iTunes, or on MP3 players other than iPod, iPhone, or iPad.

• WAV Encoder: Use if you’ll be playing your songs on a computer that doesn’t have MP3 software.

Choose a bit rate from the Setting pop-up menu (not available with Apple Lossless Encoder). In most cases, the default selection works well. If you chose MP3 Encoder, you can choose one of the following:

• Good Quality: Choose to fit more songs on a portable MP3 player with limited storage capacity.

• High Quality: Choose if you play music in a noisy environment. This setting creates files that are about 1 MB in size per minute of music.

• Higher Quality: Choose if you plan to create your own audio CDs or listen to your music with high-quality stereo speakers.

• Custom: Choose for greater control over the file size and sound quality.

Choose iTunes > Preferences, click General, and click Import Settings.

Choose an encoding format from the Import Using pop-up menu.

Choose Custom from the Setting pop-up menu.

Select the settings available for your encoding format:

• Stereo Bit Rate (AAC and MP3 only): The higher the Mono or Stereo kilobits per second (kbps), the higher the audio quality and the larger the file size. The most common bit rate for stereo MP3 files is between 128 kbps and 192 kbps. Lower bit rates are more appropriate for sound files containing voice recordings (as opposed to music).

• Use Variable Bit Rate Encoding (VBR) (AAC and MP3 only): This setting varies the number of bits used to store the music depending on the complexity of the music. This can help keep file size to a minimum.

• Sample Rate: The number of times per second that the music waveforms are captured digitally. The higher the sample rate, the higher the quality and the larger the file size. Don’t choose a sample rate higher than the rate used originally to store the music or you’ll waste space. CD quality, for example, is 44.100 kHz, so choosing a higher rate when you’re encoding from a CD is unnecessary. In general, the best choice is Auto, which uses the same rate as the original music.

• Sample Size (AIFF and WAV only): The number of bits used to store each sample taken as the music is encoded. The higher the sample size, the better the quality and the larger the file size.

• Channels: If you don’t have stereo speakers or if your audio files are monaural (mono files are about half the size of stereo files), choose Mono. If you’ll be listening through headphones or a stereo system, choose Stereo or Auto. Auto converts monaural tracks into mono files and stereo tracks into stereo files.

• Stereo Mode (MP3 only): In Normal mode, your MP3 files contain one track for the right stereo channel and one track for the left. In many cases, the two channels contain related information. In Joint Stereo mode, one channel carries the information that’s identical on both channels, and the other channel carries the unique information. At bit rates of 160 kbps and below, this can improve the sound quality of your converted audio.

• Filter Frequencies Below 10 Hz (MP3 only): Select to filter inaudible frequencies, which results in smaller, more efficient files without perceptible loss of quality.

• Smart Encoding Adjustments (MP3 only): Select to have iTunes analyze your encoding settings and music source.

• Use High Efficiency Encoding (HE) (AAC only): This setting optimizes the audio quality of highly compressed files. Select if you plan to stream audio.

• Optimize for voice (AAC only): This setting changes the bit rate based on the pitch of spoken voices. Select for importing audiobooks, not music.