PC Audio Editing

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tracks, and a good all-round general workhorse. Its methods are easily transferred to other editors.It also has a sister program, Cool Edit 2000, which has a subset of the Pro versions facilities. Thesecan be enhanced by add-on modules.

3.8 Linear editorsEditors fall into two methods of working: linear and non-linear. Linear editors can handle one stereo,or mono, audio track at a time. They operate like word processors; any editing is destructive in thata deleted section is actually deleted from the audio file (although, as with word processors, thereis likely to be an undo feature available). When saved, any cut material is lost unless a backup copyof the original has been kept.

Owing to the large amounts of data involved with audio, cut and paste are instantaneous only forthe smallest of sections. Copying a 40-minute stereo file can take several minutes. While theprocess may be much quicker than with pre-digital technology, minutes spent staring at a progressbar crossing your screen are frustrating and unproductive (see section 7.2, Blue bar blues).

3.9 Non-linear editorsNon-linear editors do not change the audio files being edited in any way, but instead create EditDecision Lists (EDLs). They dont play an audio file linearly from beginning to end; instead the filesare played out of sequence non-linearly with edits performed by skipping instantly to the nextsection. It is a sophisticated version of programming the playback of a CD, where you set the CDonly to play certain tracks but the omitted tracks are still on the disk. EDLs allow the playback toskip from instant to instant within and between tracks.

The most obvious advantage is that material is never lost. However, this can be a disadvantageas well, because your hard disk can soon become cluttered with unwanted material. In practice,some culling with a linear editor is useful before using a non-linear one.

You can have any number of different EDLs for the same audio, and thus any number of differentversions. You can decide to keep a version that you are reasonably happy with, but continue to seeif you can further improve the item. This is ideal if the same item has to be repackaged for differentprogramme outlets. A programme trail can be one edit decision list, and the broadcast programmeanother. Even in the domestic environment different versions can sometimes be useful, even if it isjust a shorter version for your mother to listen to!

While this is possible with linear editors, it is at the expense of much duplication of audio data,which can soon fill a hard disk. Only the non-linear editor can give you the opportunity to unpickedits for your new version.

Non-linear editors can also handle more than one audio file at a time, and play from differentsections of a single audio file simultaneously. In this way crossfades and mixes can be performedwithout permanently changing the original audio material.

In general, non-linear editing operations can be faster as the computer is not having to movemultimegabyte chunks of digital audio data around the hard disk. Instead, the changes in the EDLare measured in just tens of bytes.