Q: My 8GB iPod touch is only holding about 350 songs before the memory is full. I have no apps, no videos, and nothing else but music. It is all filling up from the music when I don’t have much. I already restored it as the Apple Store people told me to but it is the same still. They were no help. Any ideas?

– Anonymous
A: It sounds like your songs may be encoded in a much higher bit rate than most iPod owners typically use. Although Apple doesn’t provide song estimates for iPods anymore, you will see numbers from many other sources based on encoding music as AAC or MP3 files in either 128kbps or 256kbps. However, it is possible to encode songs in these formats at higher bit-rates, or use either Apple Lossless, WAV or AIFF formats which will produce significantly larger music files.
The MP3 and AAC formats use a technique known as lossy compression to reduce the size of your original music files by essentially stripping out audio information that most listeners would not be able to hear anyway. The result is a file that is usually about 10-20% of the size of the original, uncompressed audio track from a standard CD. The “bit rate” of a compressed file refers to how much data is stored for each second of audio, with a lower number representing a smaller file at the cost of reduced audio fidelity. To put this in perspective, iTunes originally used 128kbps AAC files as its baseline standard before increasing that to 256kbps AAC about two years ago; by comparison an uncompressed CD-quality audio file is 1,411kbps and a traditional audio CD stores around 700MB of data. Therefore, without making use of some kind of compression an 8GB iPod touch would only be able to hold the music from about 11 full-length CDs.
Apple also supports a format known as Apple Lossless, which as the name implies uses lossless compression to reduce the size of an audio file without stripping out any audio information. The result is a file that is the same quality as the original, uncompressed CD audio at approximately 50-80% of the original size.
Of course, if you’re concerned about having tracks with the highest possible audio quality, you may want to keep your tracks in a higher bit reate AAC/MP3 or even Apple Lossless format, but you will be sacrificing storage space on your iPod touch by doing so. In fact, 350 tracks is about what you should expect to be able to store on an 8GB iPod touch if you are encoding them in the Apple Lossless format.
Our iPod Storage Calculator provides more information on the number of songs you would be able to store on a given capacity iPod model at various bit-rates.
You can check the format, size and bit rate of a given track in iTunes by selecting the track and choosing File, Get Info from the iTunes menu to display the track properties.
Alternatively, you can also add Bit Rate, Size and Kind columns to your main track listing to view this information for multiple tracks at once and even sort your music listing based on these fields. You can add additional columns by choosing View, View Options from the iTunes menu.
If you want to keep higher bit rate tracks in your iTunes library but want to fit more songs on your iPod touch, iTunes 10.6 or later offers a reasonable compromise by allowing you to convert your tracks to a lower bit rate when synchronizing them onto your device. Simply connect your iPod touch to your computer, select it from the iTunes Devices list on the left side of the iTunes window, and you should see an option on the Summary page to Convert higher bit rate songs to… with the option to select either 128kbps, 192kbps or 256kbps as your preferred bit rate. This feature will leave your original tracks in your iTunes library in whatever format they are already in, but any tracks with a bit rate higher than the one specified on this screen will be automatically converted to an AAC file with the appropriate bit rate before being copied to your iPod touch.
Alternatively, if you’re more concerned about saving disk space than keeping ultra high-quality audio files, you can change your default import format by opening your iTunes Preferences and selecting Import Settings from the General panel.
This change will only affect new tracks that you import into iTunes from CD, however you can convert any existing tracks to the default format by selecting the tracks and choosing Create AAC Version from the iTunes Advanced menu. Note, however, that converting between lossy formats is generally a bad idea for audio quality; if your tracks are in Apple Lossless this is not a problem, but if you’re using higher bit rate AAC or MP3 files you’re better off re-ripping them from the original CDs.
Lastly, keep in mind that audio quality is generally subjective, and largely dependent on the equipment that you’re using to listen to your music. Although many audio enthusiasts are proponents of always using lossless files, not only is there a storage cost to this, but you’ll probably find that your ears can’t hear the difference between an original CD and a 256kbps AAC file; this is especially true if you’re using an average set of earphones on your iPod touch. Even if you’re concerned about getting the best audio quality possible, it’s always a good idea to do some basic listening tests to decide for yourself what an acceptable bit rate is. The only other advantage to maintaining a lossless library is the ability to easily convert to other formats in the future without sacrificing audio quality, effectively maintaing the tracks in your iTunes library as “masters” from which you can convert to a variety of different formats for different uses. However, the average iPod and iTunes user will rarely have any need to do this, as the MP3 and AAC formats are well established and very widely supported on any number of devices and software applications.