Live's clip warping is generally used to adjust an audio loop's timing and groove to match your song (see the 'Warp Markers, Time & Tempo' box), but its usefulness as a sound-design tool is often overlooked. For an introduction to warping in sound-design, check out the March 2010 Live workshop column. In this article, I'm going to flesh out the details in the context of some specific examples. I've created some audio examples to accompany this article, and they can be found at /sos/aug12/articles/live-tech-0812-media.htm.
You can set up clip warping in both Session and Arrangement views, but for sound-design purposes, I prefer to start with an empty set, work in Arrangement view and turn off clip looping. (If you want playback to loop, use the Arrangement's loop.) This means you can see any changes to the clip's length on the Arrangement view track while working on the details in the Clip View window. It also makes it easy to bounce the results to a new audio file, using Live's Consolidate function (Ctrl-J or Cmd-J). You can then apply more sound-design warping to the consolidated file.
Chopping a pad into regularly spaced pulses is about the easiest thing you can do, and much simpler and quicker than doing so in a sampler or sample editor (see screen 1). Start with a four-bar clip of a pad sound and place it in an audio track at the beginning of your arrangement. With the clip selected, look at the Warp panel at the centre of the Sample section of the Clip View. If you haven't changed Live's default Record/Warp/Launch preferences, warping will be turned on and set to Beats mode, and the Beats mode parameters will be set to Preserve Transients with back-and-forth looping and a transient envelope setting of 100. Click the Preserve drop-down menu (displaying the word 'Transients') and select '1/8'. Click the loop-mode drop-down menu (displaying the back-and-forth arrows) and select one-shot with the forward arrow icon at the top. Click the fade envelope numerical (displaying 100) and drag the value down to around 60. Play the clip, and instead of a steady pad you'll hear regular pulses with the same timbre and pitch contour as the original pad (see audio example 1). One thing to notice here is that when you change Live's tempo, the pulse rate changes but the timbre remains the same, as Beats-mode warping preserves the original timbre. (Other modifications, such as transposition, back-and-forth looping, and so on, will, of course, affect the timbre.)
Consolidate the pad clip with these warp settings to produce a new clip made up of the pulses. Notice that the Warp settings have returned to their default. This time leave Preserve set to Transients, but again, change looping to one-shot. Beats-mode warping with Transients as the Preserve value creates the pulses at the Transient markers rather than at regular note divisions.
You can change the pulse pattern at various points in the clip by inserting Warp markers and adjusting the waveform beneath them. For example, place a Warp marker at the bar-three grid-line (click on the grid-line and type Ctrl-I/Cmd-I). Now place the cursor over the Warp marker, hold the Shift key and click-drag right until four pulses fill the first two bars. Repeat the process at a few other bar lines with different numbers of pulses (see screen 2).
When you examine the clip in the Clip View, you'll notice Transient markers (vertical white lines or wedges, depending on the zoom level, at the top of the waveform display). Go through the clip and delete any Transient markers not at the beginning of a pulse by selecting them, one by one, and hitting the Delete key. If you find any pulses without Transient markers, click at the beginning of the pulse and insert a Transient marker there (Ctrl-Shift-I or Cmd-Shift-I).
As a final tweak, you can use the Sample Transpose fader to change the pitch and timbre of the whole clip (try octave shifts), and the Transpose clip envelope to re-pitch individual pulses (see audio example 2).
Texture is my favourite Warp mode for inflicting maximum damage. It gives you precise control over grain size and offers randomisation using the Flux setting. When coupled with extreme pitch shifts, it can completely change the character of the sound, as we'll see.
Insert a four-bar bass clip at the beginning of a new arrangement. Change the Warp mode to Texture and play with the Transpose knob to hear the effect of extreme pitch shifts with the default settings (Grain Size 65.00 and Flux 25.00). Select an upward transpose of between three and four octaves and play with the Grain Size. You'll find that sizes in the teens and 20s radically change the bass timbre. High Flux values obscure the pitch even more, to produce a whisper-like effect (see screen 3).
You can use the processed sound by itself or layered with the original. When layering, try shifting the processed clip a bit later in time (say, a 64th note). Also try reversing the processed clip and then shifting it earlier, so that the reversed transients hit slightly after the bass transients (see audio example 3).
With Texture warping, extreme time stretching is another great tool for mangling sounds. You can use this with or without transposition and the Grain Size, again, has a big impact on the results.
Start with a two-bar bongo clip. In the Warp panel, click the '*2' button twice so that the Seg. BPM value quadruples. This will stretch the clip to four times its original length when played at the set's tempo. With a large Grain Size, high Flux setting and upward transposition of an octave or so, the bongo strikes will be shredded into glassy pings. Adding a Grain Size clip envelope will further contour the sound (see screen 4).
Consolidate that clip, change warping to Beats mode with Preserve set to '1 Bar' and select one-shot loop mode. Extreme transposition clip envelopes work well with long chops like this (again, see audio example 3). Now consolidate a copy of this clip and reverse it. Play the two clips together, possibly with some pan automation; being reversed copies of one another, they will loop well.
As an alternative to using the warped clip, consolidate it and insert Warp markers for separate individual sound events. Then use Live's Slice to New MIDI Track function to create a Drum Rack made up of the slices between each pair of Warp markers. You can refine the clip boundaries and make other adjustments in the Simplers in the Drum Rack chains. See the June 2010 Live workshop column for more on slicing.
Warp markers lock positions in an audio file to positions on the set's timeline. Between adjacent Warp markers you're dealing with two measures of time: the number of samples divided by the sampling rate and the number of beats divided by the set's tempo. When those two times match up, the audio plays at its natural rate. When they don't match up, Live must resort to trickery to get the segment of audio to play in the allotted number of beats. This is called Warping.
The Seg. BPM box in the top half of the Warp panel in the Sample section of the Clip View shows the tempo required to match the number of samples between the selected Warp marker and the closest one to its left . If no Warp marker is selected, the box is greyed out. (The first Warp marker's tempo either mimics the second one's or, if there is no second Warp marker, shows the natural tempo for the whole audio file.) Changing the number in the Seg. BPM box is the same as dragging the selected Warp marker left or right to enclose more or fewer samples. Shift-dragging a Warp marker lets you align a point in the audio file to the Warp marker rather than moving the Warp marker, and this also changes the Warp marker's Seg. BPM value. To calculate the ratio between the clip's playback rate in the set and its natural playback rate, divide the set's tempo by Seg. BPM.