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Audio Software: Less Cost, More Creativity
by David Fox
Although software-based audio systems have been around for more than a decade, it is only since the beginning of 2002 that they have seriously offered an alternative to hardware systems for broadcast work, according to composer, Elizabeth Parker.
Not only are there a host of new, low-cost applications, but increasing audio quality (up to 24-bit, 96kHz) and better synchronisation with video, mean that audio-for-video work can now be done largely in a virtual studio, even on a laptop.
While DigiDesign's Pro Tools is still the leading audio editing software, with its latest HD version capable of 24/96 quality, there are an increasing number of alternatives, including music sequencers with increasingly sophisticated audio editing, such as Mark of the Unicorn's Digital Performer or Cakewalk's Sonar sequencer, which can match scrub audio and video for dropping in sounds or effects, and import QuickTime, AVI or MPEG video.
Pro Tools closest rival is Steinberg's Nuendo, which is ideal for surround sound (including the ability to add spatial reverbs giving reflections from different parts of the room) and has just recently been used to remaster a series of DVDs in 5.1 for the uncompressed surround encoding vendor, DTS. As you scrub video in a linked QuickTime window, the audio matches it.
Creatively, software also offers considerable benefits. Melodyne, probably the most powerful pitch-shifting device yet built, allows each note of a vocal (or any other sound) to be graphically manipulated, time-stretched (without altering the overall timing) and edited. A complete vocal could easily be remapped to a completely different tune without altering its character.
There are also a huge range of plug-ins, from massive virtual instruments (such as Absynth, a VST plug-in, or the Bitheadz Unity DS-1 sampler) to a whole host of digital signal processors (such as: Antares Auto-Tune, real-time pitch correction; McDSP Parametric EQ and Compressor Bank; Arboretum, with 30+ different effects; the TC Electronic's range of outboard; and Antares Microphone Modeller, which simulates the sound of 100+ classic microphones).
Anvil Post Production
Not all of these plug-ins can yet be used on Pro Tools HD, but most main ones can, says Rupert Scrivener, technical manager, Anvil Post Production, HD's first European user.
For many years Anvil, which mainly does high-end drama and feature film work, has used the PC-based Timeline Waveframe system, popular in the US but not in Europe. It has five of these and Scrivener rates them as "a very dependable system, much more stable than Pro Tools, but they don't have the same upgradability."
However, Pro Tools is now the de facto standard in post and Anvil has adopted it to avoid problems with file transfers, especially as more work was being brought in from other Pro Tools systems. "We simply have to have them." It means clients can bring in dialogue for foreign versions on CD "and be ready to go in five minutes with all the plug-ins doing what they had been doing previously." There are some plug-ins that are widely used, such as DigiDesign's own and Focusrite Reds, but with hundreds available, it would be impractical and expensive to have them all. It would also require too much processing power to run a lot of plug-ins, even though all the digital signal processing is done on Dsp Farm cards installed in the Mac.
He rates HD as a "good advance" over previous versions. "It seems much more user friendly and self configuring." More usefully, HD is "very cost effective". They didn't consider anything else.
Its higher bit rates make it future-proof, although "I don't know of any facility which is fully 96kHz compliant. There are so many issues in the way, but it is going that way," he says. Anvil uses it with its two 48kHz SSL Avant consoles, generally for 24-track work with effects or 16-tracks with dialogue, although they can also do virtual mixing if more tracks are needed. It also has Pro Tools, with the Pro Control desk, in its DVD suite. If mixing 5.1 surround sound, and wanting to keep the separation, a mono source can take up five tracks (one for each speaker). "We're always pushing the upper boundaries available on the system," he says.
Parker has written scores for hundreds of documentaries and natural history series for all the UK broadcasters, Discovery and National Geographic. On the recent BBC series, Weird Nature, she captured video clips though Adobe Premiere, synched with Digital Performer. "It all runs beautifully," she says. When she moves to the latest version of Performer, she won't even need to run Premiere.
However, having to capture each new tape does take time, so it is often simpler to just put the timecode from the VHS into Performer. "Usually everything has to be done in such a hurry, it is quicker to synch up by hand."
As she often has six to eight projects underway at once, "I can't afford to have things not work," she says, so is wary of doing everything in the computer. She is also afraid of losing the "musicality" of a piece by over-processing.
Similar concerns affect film and TV composer, Simon Boswell, whose credits include Shallow Grave, Midsummer Night's Dream and the BBC series, The Lakes. Although it is possible to do an entire mix in Pro Tools, he prefers the sound of his Neve desk and outboard equipment. He does use plug-ins, "but I'd hate to be restricted just to them."
However, since moving to software from a U-Matic locked to a 24-track tape recorder, he has noticed a ten-fold increase in set-up speed.
A lot of what he does is adjusting what he's already written to a constantly re-edited master. "Because of special effects, the film is generally changing as you work on it."
He has been using one Mac for video (output to a projector) and the other for audio, linked by MIDI Time Code, to allow for the maximum number of audio tracks. "This is not an ideal solution for locking things, but perfect for writing as it's very quick." However, he recently bought a dual 1GHz Mac, which can run video and audio at the same time without performance suffering, so he will probably dispense with the dedicated video machine. "Obviously, not having to deal with tapes is rather wonderful, but I have a growing collection of hard drives," he adds.
He has been using Performer since 1985, and feels it is very well suited to film music. Using an OMF transfer, he finishes in Pro Tools, which he finds easier to use for editing, especially doing surround sound work. Performer can do many of the same things as Pro Tools, he says, but does them differently.