Digital audio

Digital audio (frequently referred to here as just “audio”) is a simple way to record and play sounds of any type. It works like a tape recorder—you record something, then later play it back. Digital audio stores the sound as a long series of numbers. To record audio in SONAR, you have to have an audio cable connecting the audio output of your electronic instrument to the audio input on your sound card or audio hardware. If you’re recording vocals or an acoustic instrument, you need to connect a microphone to the audio input on your sound card or audio hardware.

Sound Waves

Sound waves are vibrations in the air. Sound waves are generated by anything that vibrates; a vibrating object causes the air next to it to vibrate, and the vibration is passed through the air in all directions. When the vibrating air enters your ear, it makes your eardrum vibrate, and you hear a sound. Likewise, if the vibrating air hits a microphone, it causes the microphone to vibrate and send electrical signals to whatever it's connected to.

These vibrations are very fast. The slowest vibration frequency you can hear is about 20 vibrations per second, and the fastest is around 16,000 to 20,000 vibrations per second.

Recording digital audio

To record digital audio, your computer monitors the electrical signal generated by a microphone, an electric guitar, or another source. At equal intervals of time (for CD-quality sound, this means 44,100 times a second), the computer measures and saves the strength of the electrical signal from the microphone, on a scale from 0 to 65,535.

That's it. Digital audio data is just a long series of numbers. The computer sends these numbers, in the form of electrical signals, to a speaker. The speaker then vibrates and generates the same sound that was recorded.

The primary advantage of digital audio is the quality of the sound. Unlike MIDI, a digital audio recording is very rich, capturing all the nuances, overtones, and other characteristics of the sound exactly as performed. The main drawback of digital audio is that it takes up a lot of disk space. To record a 1-minute segment of stereo, CD-quality digital audio, you need about 10 megabytes of disk space.On the computer, digital audio is usually stored in Wave files (extension .wav). There are many programs available that let you create, play, and edit these files. SONAR reads, writes, and lets you edit Wave files.

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