1122 Chapter 29
ging the loops into the program’s main soundfile view
where they can be arranged, edited, processed, saved,
and exported.
One of the most interesting aspects of a loop-based
editor is its ability to match the tempo of a specially
programmed loop soundfile to the tempo of the current
session. Amazingly enough, this process isn’t that diffi-
cult to perform, as the program extracts the length,
native tempo, and pitch information from the imported
file’s header and (using various digital time and/or pitch
change techniques) adjusts the loop to fit the native
time/pitch parameters of the current session. This means
that loops of various tempos and musical keys can be
automatically adjusted in length and pitch so as to fit in
time with previously existing loops. These shifts in time
to match a loop to the session’s native tempo can actu-
ally be performed in a number of ways. For example,
using basic DSP techniques to time-stretch and
pitch-shift a recorded loop will often work well over a
given plus-or-minus percentage range (which is often
dependent on the quality of the program algorithms).
Beyond this range, the loop will often begin to distort
and become jittery. At such extremes, other playback
algorithms and beat slice detection techniques can be
used to make the loop sound more natural. For example,
drums or percussion can be stretched in time by adding
additional silence between the various hit points within
the loop at precisely calculated intervals. In this way,
the pitch will remain the same while the length is
altered. Of course, such a loop would sound choppy and
broken up when played on its own; however, when
buried within a mix, it might work just fine. It’s all up to
you and the current musical context.
The software world doesn’t actually hold the total
patent on looping tools and toys; there are a number of
groove keyboards and module boxes that are on the
market. These systems, which range widely in sounds,
functionality, and price, can offer up a wide range of
unique sounds that can be quite useful laying a founda-
tion under your production. In the past, getting a hard-
ware grove tool to sync into a session could be
time-consuming, frustrating, and problematic, taking
time and tons of manual reading. However, with the
advent of powerful time and pitch shift processing
within most DAWs, the sounds from these hardware
devices can be pulled into a session without too much
trouble. For example, a single groove loop (or multiple
loops) could be recorded into a DAW (at a bpm that’s
near to the session’s tempo), edited, and then imported
into the session, at which time the loop could be easily
stretched into time sync, allowing it to be looped to your
heart’s content. Just remember, necessity is the motherFigure 29-31. Seinberg’s Sequel music software. Courtesy
of Steinberg Media Technologies GmbH, a division of
Yamaha Corporation, http://www.steinberg.net.
Figure 29-32. Ableton live performance audio workstation.
Courtesy of Ableton, http://www.ableton.com.A. Arrangement view.B. Session view.