Digital Audio Production 59720.1.2 Low-Cost Audio Editing
Most audio capture cards like the Creative Labs Soundblaster come bundled with a
primitive sound-fi le editing software. Usually this permits a “ butt-join ” edit (the exact
analogy of a razor blade splice) between different sound fi les or between data loaded
onto the clipboard in rather the same way as a word processor works on text fi les. In fact,
Creative Labs ’ Wave Studio utility is quite powerful and affords some manipulations
(such as the ability to operate on left and right channels of a stereo signal separately) that
exceed the capabilities of some low-end professional editing software. However, the big
disadvantage with Wave Studio is that it does not allow for nondestructive editing. An
inexpensive and truly excellent package is authored by Minnetonka Software Inc. and
is known as FastEddie. This “ value ” package permits nondestructive editing to sample
accuracy, preaudition of edit points, the ability to mix fi les, time “ stretch ” or compress
the WAV fi le, and normalize gain so that a WAV fi le may be increased in gain just enough
so that the largest excursion on the fi le is brought almost to within clipping level, thus
maximizing dynamic range. The utility can also be used to generate audio effects such
as echo and reverb and reversal of the sound fi le so that it plays backward. In order
to facilitate the judgment of edit points, most editing software provides an on-screen
waveform display. This may be zoomed at will: IN to examine individual samples and
OUT to reveal musical sections or the whole fi le.
An example is shown in Figure 20.2 , which is an off-screen capture of a FastEddie
window. The highlighted sections in the lower, read-only part of the window are ready
for editing in the top editing part of the window. Given its price, FastEddie has a number
of very professional features, among these is the ability to cross-fade at edit points rather
than to produce a butt join ( Figure 20.3 ). The advantage of this feature is due to the
complex nature of musical sounds. Even if an edit is made at a precise point in a musical
score, a discontinuity is produced in the audio waveform. This discontinuity usually
manifests itself as an audible click or “ bump. ” The use of cross-fading ameliorates
these effects. FastEddie also provides facilities for producing fade-outs and fade-ins on
complete sound-fi le data.
20.1.3 Professional Audio Editing
For professional music editing, most sophisticated editing systems still exist,
ranging from the reasonable to the very expensive. At the higher end, the platforms