Warp vs. Flex Time vs. Elastic Audio
Live, Logic, and Pro Tools Stretch Time
In the beginning, there was Beat Detective. Pro Tools detected your waveform's transients and sliced the audio at each, allowing you to shift each slice at will and relieving your drummer of the worry of pesky things like timing. There's only so much that could be accomplished with a chopped-up waveform, though, and drastic shifts or changes in tempo resulted in a gated effect and choppy beats. It would be great if you could, you know, just make that snare hit longer.
What's that? You can make it longer, and have been able to do so since the invention of tape speed? Well, sure, the snare hit is longer after you slowed down the tape, but now it sounds like a bass guitar. You want a snare.
Enter the algorithmic minds of software engineers and their modern computer gizmos. With today's processing power, it's possible to stretch and shrink audio while retaining its original pitch by screwing with the 1s and 0s before they're converted to sound. There's plenty of ways to skin that proverbial cat, though, and some solutions sound better than others. The perceived quality of the algorithm is also highly dependent on the program material, and unless you find the right combination, your beat could sound like the zipper on your Levi's.
In this video, we compare the time-stretching solutions of three popular DAWs: Ableton Live, Apple Logic Pro, and Avid Pro Tools LE. The program material is a nifty drum beat by the band Dredg.
The beat's timing is spot-on, so no additional transient markers are necessary to stretch and tame it's tempo. We simply told each piece of software to make the entire 8-bar loop longer and shorter, and we looked at a few different algorithms on each. Now, most of these algorithms weren't designed to make changes this drastic, and, in fact, Logic seems to suffer especially by the lack of an algorithm comparable to Live's Complex or Pro Tools's X-Form.
The video and audio are below. Have fun.
(Remember that previewing the audio will reveal artifacts introduced by the mp3 conversion. For the most accurate interpretation of the results, download the wav files.)