General Ripping Principles

Before you can encode a single bit, you’ve got to get the music you intend to compress into your computer. This may be accomplished by piping the signal directly into your machine through your sound card’s Line In jack (either from a mixing board or from home stereo components) or by extracting tracks from compact discs by way of your machine’s CD-ROM drive in a process known as “ripping.”

Ripping from Compact Discs

When you insert an audio CD into your machine’s CD tray, then try to view its contents through your file manager (such as Explorer), you’ll notice that all you see is a collection of 1 KB tracks labeled “Track1.CDA,” “Track2.CDA,” and so on. Drag one of these tracks to another location, and you’ll find that you haven’t copied that track’s audio data to your system at all. This is because CDA (Compact Disc Audio) tracks aren’t actually audio tracks—they’re just “handles” that tell the operating system where on the CD to find the actual audio bits. Technically speaking, what you see when you view a folder full of CDA files is the CD’s “table of contents,” which tells the CD player at which byte offsets to find corresponding PCM data on the disk. By default, most operating system’s file managers will only give you access to CDA handles and not to actual audio data, so you need to find a way around the situation if you want to encode those tracks.

You could take the long, cumbersome route and play the audio CDs through your machine’s CD player ...

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