Of the dozens of music-production software titles currently available, Ableton Live is unique. With its roots in live performance, it presents the user with a fluid, flexible interface that often makes it feel more musical instrument than recording studio. Still, version 5 excelled at both performance and recording, with comprehensive MIDI/audio editing and mixing built around its live performance toolset. Version 6 continues in this vein, with a range of new features on top of an otherwise untouched user interface.

According to Ableton, the most requested feature was video support. Live 6 obliges with the ability to import QuickTime videos and, in characteristic fashion, it includes an unusual twist. Warp Markers can be added to QuickTime files in the same way as they’re applied to audio recordings, but are used so that the tempo of the music follows cue points in the video. This makes it easy to line up audio events with video cues. The video’s soundtrack is processed just like any other audio channel, and it’s possible to trim and even combine video files on a timeline. However, it’s disappointing that videos can’t be chopped and rearranged on the fly in Session view or piped to a FireWire port as a DV stream.

Instrument and Effect Racks increase Live’s signal-routing flexibility. As with Device Groups used in version 5, a Rack can consist of a string of instrument or effect plug-ins for easy saving and recalling. However, Racks can also comprise plug-ins routed in parallel.

This makes it possible to create complex multi-effects configurations but, more importantly, it allows instruments to be combined on a single channel. These can be either layered for rich, complex sounds, or split by key or velocity so the sound changes depending on the pitch or velocity (loudness) of the MIDI performance. Eight macro controls can be set to control any combination of other controls within a Rack, either for quick access to key functions or to create instruments or effects that morph with the turn of a single knob. Racks enhance the scope of the built-in basic sampler instrument (known as Simpler), and will be invaluable for anyone using Live to perform with a MIDI keyboard on stage.

The Essential Instrument Collection is a 14GB library of instruments for Simpler that’s bundled with the boxed version of Live 6. It’s surprisingly light on abstract and electronic sounds, and instead concentrates on realistic emulations of orchestral and other acoustic instruments. The quality is broadly excellent, with highlights including a grand piano and orchestral harp. All the instruments are multi-sampled at various pitches and volumes, and many use separate samples for the body and tail of a note, which gives a realistic taper to the end of bowed string notes and a clunk after harpsichord notes. However, the library is patchy, with a bassoon that leaps from mellow to foghorn-like as the MIDI velocity increases, and a few other less-than-pleasant presets. Whereas most of Ableton Live is amazingly responsive and reliable, loading some sounds from the library also takes quite a few seconds and playback can be prone to glitches for the first few seconds.

Live 5 was well stocked for interesting audio effects, but its one weakness was analogue-style distortion. Version 6 fixes this with a Dynamic Tube effect, which offers everything from subtle valve warmth to a trashed guitar amp. Controls such as Envelope, Attack and Release are unorthodox on a distortion effect but provide an unusual level of flexibility. Also, the improved Saturator offers a spectacular array of unusual controls and a sonic palette to match.

Other new features include dual-core and multiple processor support, improved support for MIDI hardware and the ability to warp the timing of multiple tracks simultaneously, which is useful for manipulating entire compositions or multi-microphone drum recordings. The mixer finally includes a numerical readout of each channel’s level, both in terms of the fader position and its peak output level, clearly showing when an output buss is distorting. However, these are only visible by expanding the fader section’s height rather than by default, so it isn’t the easiest feature to find.

Live 6 is a worthwhile update to an already excellent program. Once again, many of the new features are geared more towards studio production than live performance, but these don’t stand in the way of Live’s aptitude for use on stage. In this role, it remains peerless. In the studio, the competition is tougher, but video support and the Sound library means the gap between Live and options such as Cakewalk’s Sonar is smaller than ever. The price continues to creep up but for software this sophisticated, flexible and fun, it’s money well spent.