Ableton Live review

Ableton is the unlikely moniker of a new German company founded by members of computer music artist collective Monolake. The group was well known for its ground-breaking live shows, so it's hardly surprising that the company's first product, Live, is designed with live performance in mind.

Like Sonic Foundry's well-established program ACID, Live is a loop-based sequencer. Songs can be constructed by dragging pre-recorded loops from a browser into Live's Arranger view. Tracks are stacked vertically on screen, with the cursor scrolling from left to right, playing the loops you've dropped as the cursor crosses them. Nothing revolutionary here.

However, Ableton has a second editing mode, called Track view, and this is where things get interesting. In this window, tracks appear as columns. These form a grid with the horizontal rows, each of which is called a Scene. What's the significance? Most compositions, live or recorded, are divided into convenient sections, such as intro, first verse, bridge, first chorus and so on. Each Scene can contain a number of audio clips; for example, the intro may contain a percussion loop that you drag into the intersection of the Track 1 column and the Intro row. The first verse might add a drum loop in the Track 2 column and guitars, vocals and so on in other columns, all on the row labelled First Verse.

If you press the Play button on the Intro row, it will play all loops on that row according to their individual settings - either looped or 'one shot' with a variety of trigger modes. When ready, you simply click the Play button on the First Verse row - the Intro Scene will cease playing and the first verse will begin. You can also assign keystrokes or keys on a connected keyboard to trigger Play buttons, which makes live use a doddle.

As well as triggering whole Scenes at once, you can also press the Play button next to individual clips, dropping loops in and out of the composition live. There are a number of different trigger modes; for example, if the clip is set to Toggle, clicking the mouse button once will start the clip, and a second click will end it; Gate will play the clip only while the mouse button is pressed down, and so on.

What makes this system doubly clever is that you can specify the quantisation of clip triggering. Click on a Play button while quantisation is set to a bar and Live will wait for the beginning of the next bar before commencing playback; if set to quarter bar, it will begin playback when it hits the next quarter bar. In this way, you can drop clips or scenes in and out with perfect synchronisation.

Live has a superb audio engine at its heart. When you drag an audio clip into the main window, the program analyses it, calculates its original tempo, inserts markers within the audio clip itself showing where the beats fall, and then stretches or compresses it to fit the song's master tempo. Exactly how this is performed isn't entirely clear; I suspect it's using a mixture of the technique applied by ReCycle - where slices between the markers are shifted in time to fit the new tempo - and traditional time stretching as applied by ACID, which resamples the clip to a new tempo on the fly. In either case, it works extremely well.

The Track and Arranger views are independent - the former is suitable for composing a new track conventionally, while the latter is aimed at live use. However, you can record a live performance from the Track view to the Arranger view, then fine-tune it. This is an extremely fast way of building a track from scratch. You can even pipe ReWire-compatible applications such as Reason directly into the mixer, giving you synthesis tools as well as loops for track construction.