Audio CDs — compact discs — are a digital format, which makes them one of the easier media to digitize. You'll need a computer with a CD-ROM drive. (If your computer doesn't have one built in, a external one is fine.) You'll also need digitization software. For MacOS, iTunes, which is included with the operating system, does the job nicely. For Windows, Exact Audio Copy is the best audio CD ripping program. Linux users can use cdparanoia.
Digitizing Audio CDs with Mac/iTunes
iTunes is included on your Mac, and does a fine job of digitizing audio CDs. (Technically, it's not digitizing, because CDs are already digital. It converts the CD audio to separate audio files, a process colloquially known as ripping.)
We hesitate to give precise directions to click on this command and that button, because Apple seems to enjoy changing iTunes a little bit with every version. So take the following as a general guide. From the iTunes menu, choose Preferences. In the General tab of the Preferences pane, you'll see some settings about what to do when an CD is inserted. If you'll be digitizing several CDs, change the setting to "Import CD and Eject". Click the Import Settings button, where they hide the good stuff.
In Import Settings, you can choose which file format for your resulting audio files. Apple Lossless Encoded sounds great — lossless is wonderful — but it's a proprietary format that may be tricky to decode in 50 years. MP3, on the other hand, is a widely-used, open format that will be easily decodable into the far future, so that's probably best for most projects. But don't crimp on bit rate — higher bit rate makes better sounding files, but larger files. Doesn't matter, disk space is cheap. Even for the digitization of the lowest quality source material, we suggest using the highest MP3 bit rate that you can: 320 kbps. (If those files are too big for your immediate use, you can always re-encode at a lower bitrate — but keep the big, high-quality files around in case you need them in the future.) The other settings are fine at their defaults, of automatic sample rate, joint stereo, etc. (Help? Smart Encoding Adjustments? Filter Frequencies Below 10 hz? I dunno but tend to guess no. Savetz (talk) 00:32, 27 August 2015 (UTC))
After the audio files have been ripped info iTunes, you can see them in the My Music list. You should add metadata to the files — titles for the tracks, artist, year, notes, etc. It's not necessary to fill out every field — some aren't appropriate or relevant for every type of audio file — but you'll probably at least want to give them proper titles. You can tweak the metadata for a single file by selecting it and choosing Get Info from the File manu (or pressing Command-I.) You can also change the metadata for multiple files at once by selecting several then choosing Get Info.
Digitizing Audio CDs with Windows
Digitizing Audio CD with Linux
Most tools for digitizing Audio CDs on Linux use the same backend tools for ripping (cdparanoia, cdda2wav, etc) and encoding (depending on format lame, vorbis-tools, flac, etc). This gives users the freedom to choose the frontend they like without having to worry about the quality of the encoded files. As for the encoding format, the best choice for a lossless format should be FLAC (Free Lossless Audio Codec), as it is an open format with a free reference implementation, so it should be readable for a very long time. Also most software and hardware players support it (don't know what the status on Apple devices is, and most software players need the codecs installed).
The simplest tool (that's also easier to use then using cdparanoia and an encoder directly) is abcde (A Better CD Encoder). It should be available for every Linux distribution. abcde is strictly a command line tool, which makes it usable on every system that can read CDs. Before starting to rip some things in the config should be edited. To do this either copy the system wide config /etc/abcde.conf to your home or edit the system wide config with the proper rights (for most people the former is the better way). The config file has many options and is well documented with comments in the file, so I'll only point out the most important settings you'll probably want to change.
- CDROM: device you want to read CDs from, if you want to use multiple drives specify the most used here and specify the others with the command line option -d
- OUTPUTDIR: this sets were al the encoded files will go, default is the directory where abcde was called from
- OUTPUTTYPE: file format of the encoded files, fill in flac here to get flac files. Mutiple comma seperated formats produce one file for each format specified
- OUTPUTFORMAT: format of the directory and file names of the output files, default is creating a folder named after "artist name - album name" and in there files with the track number seperate with a period from the track name