Traditionally, instruments such as guitars, drums and bass were needed to make music to record to a CD. These days, electronic music can be made using only a computer to replicate these instruments. You can use live instruments or virtual ones to complete a song or album to record a CD. Plug your real instruments into a USB or FireWire sound card and use the included software to multi-track, which allows you to layer instruments over one another for a band effect. Pro Tools and Emagic's Logic program are two popular recording suites used for recording CDs.
Microphones are often needed to record vocals and other instruments when making a CD. You can plug a microphone into a pre-amp. You can give it a nice sound to record with on a stand-alone recording device or with software made specifically for recording. Acoustic guitars often sound great using a microphone to record. Guitar amps always sound better recorded with a microphone, such as the Shure SM57, rather than directly to the sound card.
After you have recorded your band or musical project, you must mix the sounds together to get a band-like sound. Making sure that the vocals are loud and clear is important to the sound of a CD, but mastering the final product is necessary. Mastering is the final equalization that is done to the stereo mix. Volume is often increased during the mastering process as well as compression, which makes the overall sound more even. Mastering software is available from Ozone and Sonic Foundry, but many mastering engineers use outboard gear for this task.
When your music is finalized through the mastering process, you can now burn it to a CD. This is the final process in making a CD. Most computers have CD burners built-in, so making that CD has never been so easy. Stand-alone recording devices often also have CD burners included. If not, you can upload the file to your computer and use your burner to make a CD as well. You can also send this CD to a duplication company to have CDs made of your music which include artwork and printed lyrics.