A question on data integrity from Michael –
“I notice when Toast Audio Extractor creates AIFF files from a CD, it carefully writes new files from the audio data in a stream. My question is this: if I copy those AIFF files from one drive to another, assuming the copy operation is successful, do I risk degrading the audio data? In other words, is it just a matter of a duplicating a digital file like any other at that point? It happens awfully fast, compared to the extraction.”
To get at the heart of this question, it’s important to understand the difference between the audio data that is on an audio CD and the form of audio data that an AIFF represents. One of the reasons the extraction of audio from a CD takes longer than duplicating an AIFF file is that the file format on a CD (often seen as .cda on a PC, not usually signified on a Mac) has to be converted into the AIFF in the first place, that is if you want to actually be able to edit it. It’s kind of like having a music translator inside your computer. First, the computer has to ‘listen’ to the CD audio (at whatever speed your CD-ROM can play it, i.e. 4x, 8x, etc.), then it has to translate it into a file format that can be manipulated. Once it’s in that format, duplicating it is, in fact, just like duplicating any other digital file at that point, as you suggested. Another reason the extraction takes longer is simply due to the fact that accessing data from a CD-ROM drive just generally takes longer than accessing data from a hard drive (this difference is usually miniscule, but still noticeable with large bits of data, like audio). This has more to do with the access time of the CD-ROM drive than the data throughput of the bus it’s on, just to clarify.
One of the main things that will more greatly impact data integrity is drive fragmentation, which is the single best reason to frequently back up ALL of the data on your computer that you wouldn’t want to lose. If you’re worried that copying an audio file might have had detrimental effects, listen to the copy and give yourself some peace of mind. Assuming you can trust your ears for the critical listen, that’s when you tell if you got an accurate reproduction. And just so we say it one more time, store your audio on it’s own dedicated drive! It helps to reduce fragmentation problems when all of the data on a drive is of the same variety.