Sound Design Workshop: A Different Slice

May 1, 2009 12:00 PM, By Len Sasso

           
 

ENHANCE YOUR BEATS WITH STUTTER EFFECTS

Stutter effects slice incoming audio into discrete chunks and then manipulate those chunks in various ways before spitting them out, usually with some tempo-synced delay. The simplest example arranges the slices in a different order while ensuring that only one slice plays at a time. More-complex options include reversing, slowing down, pitch-shifting, rapidly repeating, and other DSP effects.

Stutter effects are most often applied to percussion tracks, but here I'll discuss some interesting alternatives. I'll use three different plug-ins for my examples: SupaTrigga (Mac/Win; free) from Bram de Jong of Smartelectronix, Ableton Live's built-in Beat Repeat (Mac/Win), and Stutterer from the Cycling '74 Pluggo collection (Mac/Win; $199).

Get a Grip

To understand how a particular stutter effect works (and they often seem inscrutable at first), start by feeding it a recognizable sequence of medium-length notes spaced the same distance as the slice size. Then manipulate the plug-in's parameters one at a time to discern their effect.

With SupaTrigga, for instance, set the granularity to 8 slices/measure and record a major scale of 16th notes at eighth-note intervals. Set all the sliders full left, then play the clip while increasing the Rearrange Prob. slider. You'll notice that more and more notes are out of place but that even at 100 percent, only about half the notes are rearranged, and never the first two (the inscrutable part). Increase the remaining sliders individually and in combination, and you'll immediately grasp how this plug-in works. Notice that except for Silence, processing is applied only to rearranged notes (see Web Clip 1).

Stutter effects are a great way to add interest to repetitive short grooves. To keep the effect subtle, I use SupaTrigga as a prefader send effect, and I'll often feed it from two or more tracks. I'll then automate the track and return levels to produce variations that don't conform to the groove length (see Web Clip 2).

Repeat After Me

With Live's Beat Repeat, you focus on a specific time slice within an interval ranging from a 32nd note to four bars. When the interval selected is greater than one bar, only the first bar is processed. You can filter, repeat, repitch, and decay the captured slice. You introduce an element of chance into Beat Repeat by decreasing the Chance setting and increasing the Variation setting.

Because Beat Repeat zeros in on a single time slice, you'll often want to use several instances of the plug-in, and the easiest way to do that is to use a Live Effect Rack and insert the Beat Repeats in parallel chains. Then set each Beat Repeat's output mode to Gate so that it outputs only the processed audio. Use the rack as a send effect or add an empty chain to mix in the original audio, then use it as an insert effect.

In Web Clip 3, I've used Beat Repeat to mangle a speech clip. A handy trick for this kind of processing is to set the clip's tempo so that the phrase fills one measure, then focus Beat Repeat on the fragment you want to process. Beyond stuttering repeats, you might use Beat Repeat to add subtle accents and transpositions to music tracks (see Web Clip 4).

The Utter Stutter

FIG. 1: Here the left channels of two instances of Stutterer are used to process the left and right audio channels.

Cycling '74 Stutterer is the ultimate stuttering effect; it gives you complete control over separate left- and right-channel stuttering. Unfortunately, two important right-channel features — freeze and the pitch graph — don't work, so you're better off using a separate instance for each channel (see Fig. 1).

Stutterer has three critical settings: stutter time, autotrigger time, and number of stutters. Both times are measured in milliseconds, so for tempo-based results you need to make your own calculations. For example, at a tempo of 120 bpm, the settings on the left side of Fig. 1 will capture a 3-beat (1,500 ms stutter time) slice of audio from each bar (2,000 ms autotrigger) and repeat it once (1 # of stutters). You can also turn autotriggering off and click on the buttons at the top center of the GUI to capture slices manually. The graph in the middle sets a pitch contour for each stutter relative to the gray part of the slider to its right.

Stutterer is especially useful for shifting time relationships between a processed and unprocessed track within a mix. In Web Clip 5, for instance, only the guitar track is processed, and it uses left-channel 1-measure autotriggering, right-channel ?-measure autotriggering, and quarter-note stutters.

Len Sasso is an associate editor of EM. For an earful, visit his Web site at swiftkick.com.