Digidesign Pro Tools 4

With impressive improvements in power, speed and flexibility, Digidesign's software upgrade for their flagship digital audio production system keeps them ahead of the pack. PAUL D LEHRMAN wonders where the catch is...

Pro Tools 4 is a software‑only upgrade for Digidesign's industry‑leading studio‑in‑a‑Mac, and its myriad new features, enhancements, and general fixes are for the most part successful and welcome. Always known as a brilliant editing platform, Pro Tools' new version brings the quality of its mixing, automation, signal routing and processing functions up to the same exalted level.

The new features would fill a book — several, in fact: the manual (just for the software — the hardware gets its own documentation) runs to over 400 pages. We covered a lot of these features in our preview (SOS December 1996), so what I'll do in this review is to hit the highlights, and also point out some of the places where things aren't quite what they could be.

Hardware & Installation

While Pro Tools 4 is Digidesign's flagship product, it's now available over a wide range of price points. The cheapest way in is to use it without any additional hardware, in 'PowerMix' mode. For this you need a PowerMac with at least 32Mb of RAM, taking advantage of the computer's internal 16‑bit, 44.1kHz sound engine (see 'Hardware Options' box). To get all the features in the new software, however, you have to have a full‑fledged Pro Tools III system, which consists of a Disk I/O card, a DSP Farm card, and an audio interface. You also need an external disk drive, dedicated to audio, which is hooked up to the Disk I/O card. Digidesign say that you must have Apple's System 7.5.3 or later to run the 4.0 software, but I had no trouble at all running it with System 7.5 on a 100MHz 601‑based clone. The new software will not run on older Pro Tools '442' systems, nor on Audiomedia II cards

Installing the software upgrade is easy, since it now comes on a CD‑ROM (floppy disks are available on request). The process, however, takes a little longer than you might expect, and seems to stall at one point. The reason is that some rather brutal housekeeping is being done on your hard disk: in order to guarantee that the installation is successful, the procedure 'idiot‑proofs' your system disk by removing all traces of older versions of Pro Tools — and not only the software: all Digidesign INITs and Sound Drivers, as well as Opcode's OMS MIDI management system and Apple's QuickTime, both of which are now required, are replaced with new versions. The old files are not just put in a disabled Extensions folder — they are erased. Fortunately, you get a warning that tells you that if you want to save any of them (which you will, if you're using other software, such as BIAS' Peak, that doesn't like these versions) you'll have to move them not to a separate folder, but onto another disk.

Displays

The first thing you notice after launching the software is that the edit screen, where tracks are viewed in a linear fashion, has become quite a bit more complicated. It's now possible to re‑size tracks individually (there are five size options), so you can shrink the ones you're not working on and blow up the important ones to Sound Designer size, or even choose not to show particular tracks at all. Sends and inserts can be included in the edit screen, which means that it's quite possible to do a session without ever opening the Mix window.

You also notice that the increased screen complexity hasn't affected performance — on the contrary. On a Power Mac, at least, the program feels a lot faster and more fluid than previous versions. Most of the code has been made Power PC‑native, which provides a tremendous boost to screen redraws (the SMPTE window — now available in a 'big counter' version — and the level meters have lost their annoying lurching quality) and mouse response. The screen now scrolls smoothly as the audio plays, overcoming a limitation of previous versions. I didn't get to test the software on a 680x0 Mac, but I would imagine that the benefits are not nearly as obvious.

On the other hand, the complexity does add greatly, at least when you're first learning the program, to the confusion factor. There are so many Preferences (five pages of them!) and various other kinds of toggles, that a new user could spend a lot of time quite befuddled over why the program is behaving in the way it is.

Once you set up your edit window, you can store its configuration — zoom settings, pre‑ and post‑roll times, track heights, show/hide toggles, and/or group enables — in any of 200 memory locations, along with current time and region start and stop times.

The region list has become much more flexible, allowing you to see source file names and/or disk names in addition to region names. Regions can be sorted by name, start time, stop time, length, date, or disk location. Most of the housekeeping chores dealing with regions have been moved to a sub‑menu within the window itself, which makes a lot of sense.

One thing that hasn't changed, unfortunately, is that when you are using plug‑ins such as EQ, compression or reverb, you can see the parameters of only one plug‑in at a time — so, for example, you can't compare EQ settings on two channels. On the other hand, if you want to make sure that two modules are identical, you can copy (or save) the settings from one and paste (or load) them into the other.

Over at the Mix screen, where the tracks are shown as faders on a console, you now have the option to cut the width of all the faders in half. While the names on the faders are abbreviated when you do this, it lets you see twice as many faders (27 of them on a 17‑inch screen) without scrolling, which is a very welcome improvement.

Record And Playback

There are a number of key record options in this version.

• Loop Record, a familiar feature in MIDI sequencers, lets you automatically repeat a section of a track, laying down a new sound file each time. When you're done, you can retrieve the takes you want from the regions list and assemble a 'comp' track from bits and pieces of each. A new pop‑up menu shows you only the track regions that have the same time stamp as the one you're working on, to help you to select the right takes from the list.
• QuickPunch lets you instantaneously record‑enable a track during playback, and punch in and out on the fly. Up to 100 punches can be made, on any number of tracks, in one pass.
• Record Safe prevents selected tracks from going into record mode.
• Half‑Speed Record does just what you'd think: if you've ever overdubbed a track at 15ips on a 30ips multitrack tape, you'll know how this works. This feature appears only in the Keypad Shortcuts part of the documentation, although it isn't that hard to comprehend.
• Destructive Record erases everything on a track that's 'underneath' a new take, so that you don't keep piling up new files and regions as you do re‑takes.

A new playback feature, which was apparently specifically requested by the BBC, is 'shuttle lock', which allows you to use the computer's numeric keys to specify any of nine speeds of playback, forward or backward. I find this a little clumsy, but it could come in handy once you're used to it (and if you don't have an external transport controller).

One of the more annoying features of the old Pro Tools was that whenever you changed anything on the edit screen, playback would stop. That's now history. Not only can you scroll and change views on the fly, Pro Tools 4 also lets you edit audio while in playback, just like a MIDI sequencer. You can change TDM and automation parameters, drop in new regions, switch edit playlists, nudge regions, and even change the tempo map while the audio is playing. (If you have a MIDI metronome playing, however, and you change the tempo map, the metronome doesn't reflect the new map until you stop and start playback again.) You can even — if the 'Active in Background' toggle is on — switch into another application entirely. You'll have to turn 'Active in Background' off, however, to use any program that accesses the audio hardware, such as Sound Designer or Studio Vision.

There are a few restrictions on what you can do while audio is playing: you can't change the type of plug‑in on any channel, or open up any new plug‑ins, and when you disable a track's automation, you can't turn it back on again without stopping playback. Also, when you're moving around the screen during playback the cursor doesn't always change when it should on my 100mHz machine — you might find yourself trying to move a window with an I‑beam text cursor instead of an arrow. Digidesign say that this is related to the speed of my computer.

Automation

Some of the most significant changes in the software are in the area of mix automation. Instead of just volume and pan, Pro Tools 4 gives you total snapshot and dynamic control over all mix parameters, including EQ, solos, mutes, and send levels, as well as any or all of the parameters of TDM plug‑ins (see 'Plug‑Ins' box). As with volume and pan, when you're in 'auto record' mode and you change a parameter that's been designated as automatable — either using an on‑screen fader or an external controller (see 'External Control' box) — that change becomes part of an automation 'playlist', which is simply a list of instructions with time stamps. The nomenclature is a bit clumsy, because nowhere is there an actual list to look at — it's leftover terminology from Sound Designer, where you really do see the information in list form.

The automation playlist is separate from the track playlist — the one that determines the order in which the sound files on a track are being played — and can be edited separately, although when you cut and paste a track playlist, the automation goes with it. One of Pro Tools' best features has been that you can have an unlimited number of edit playlists on any track, which allows you to assemble alternate takes into a 'comp' track. However, you are only allowed one automation playlist per track, so those alternative takes hadn't better need different levels, or sends, or EQ settings. You can always create new tracks and mute the ones you don't want to hear, but if you're using plug‑ins this can eat up your DSP power quickly. Another workaround, suggested by Digidesign, is to create an auxiliary track and buss the comp tracks to it. Perhaps a future version will allow multiple automation playlists, which could be attached to specific edit playlists, or even mixed and matched.

Again, as with volume and pan, all automated parameters can be displayed and edited as line graphs on the edit screen, so if you want to draw in a long, slow change in a delay line's mix level, or put a wah‑wah effect on a track by wobbling the center frequency of a band‑pass filter, you can do it graphically, as well as in real time. Trim controls can be used to raise or lower the level of a parameter over time, while preserving individual moves, and automation can be copied from any track and pasted to the same parameter in an identical plug‑in on any other track. Using a special paste function, you can even clone automation moves to a different parameter, or to a parameter in a completely different type of plug‑in.

Unfortunately, you can still only view the automation data for one parameter at a time (volume, pan, sends, toggles, or processing) on any particular track. So even though, for example, you can see how an EQ's centre frequency moves or how its gain changes, you can't see both simultaneously. One way around this, if you're automating a linked stereo pair, is to display one parameter on one channel and a different one on the other, but that means temporarily un‑linking them so that you can set up the different views.

Automation moves are recorded every 5ms, which can result in a lot of data, and the manual warns that, in particularly dense situations (although I never encountered this), the automation data may clog up and not play at the right time (sounds suspiciously like 'MIDI choke'). A System Load meter is provided, to warn you when this might be the case, and there's a four‑level 'Thin Automation' function, similar to the 'Thin Controllers' feature in many MIDI sequencers, to address the problem. Since the slopes between automation points are maintained (unlike with a MIDI sequencer, which can only record discrete values), smoothness of automation within a thinned track should never be adversely affected.

Solos and mutes now work intelligently, so that soloing a reverb, for example, doesn't shut off all of the inputs to that reverb. As has always been the case with Pro Tools, however, there's a delay that varies inconsistently, from about 1 to 2 seconds, between the time when you un‑mute a track and the time when the track actually sounds, whether you do this manually or automate it (again, this may be down to CPU speed). To add to the problem, I was able to get the software to refuse to un‑mute a track at all — I had to close and re‑open the session to hear it. On the positive side, this is the only serious bug I found in several weeks of testing. Digidesign are apparently working to fix it in the next update, and suggest another workaround: close the plug‑in, open and close another, then return to the original.

Touch, Latch & Groups

Besides Read, Write and Off, the software automation provides two special modes for updating moves, similar to those found in megabuck moving‑fader consoles. One is called 'Touch', and is an overdub mode: automation is recorded only if the fader is actually being touched, and when you take the mouse away the fader glides back to where it's supposed to be. The glide time is programmable. The other mode, 'Latch', starts recording automation as soon as you move a fader, and only stops when you stop playback, at which time a new automation event is written to bring the fader back to where it was — again, at a programmable speed. A nice touch is on‑screen null indicators, to show you the current position of a fader being recorded relative to the previously‑recorded position.

Faders can now be grouped, and groups nested within each other or overlapped. Up to 26 groups can be defined, and they can be enabled or disabled, individually or globally, without changing their configuration. Moving any fader in a group moves all of them, and they all move proportionately to each other. Besides automation groups, you can define editing groups, within which slicing and dicing one track affects all of the others. Any group can be designated as an edit group, or an automation group, or both.

Editing

A significant change in Pro Tools 4.0 is that destructive file editing is now available inside the program itself. In previous versions, in order to do a destructive cut and paste, a gain change, a reverse, or a pitch change, you had to export the file to a separate program, such as Sound Designer II, mess about with it there, and then re‑import the altered audio back into the session. Pro Tools 4 has included many of Sound Designer's capabilities in a feature set called Audiosuite. Edits can be made even while the file is playing, although the alterations don't occur in real time — you'll hear them next time you play the file. Altered files are conveniently left where they are in the session. You can have the new file overwrite the old one on the disk, or save it under a new name; regardless of which you choose, you always have Undo capability. A terrific convenience is that multiple tracks and regions can be selected and processed by Audiosuite in batch mode.

Since Audiosuite functions don't depend on DSP hardware, they will run with any version of Pro Tools, including PowerMix. This also means that you can perform as many Audiosuite operations as you wish on a session without using up your DSP power — though it may take a while.

Audiosuite, like TDM, can expand its capabilities through the use of plug‑in modules. Audiosuite plug‑ins, however, are not the same as TDM plug‑ins and, unfortunately, older Sound Designer plug‑ins can't be used with Audiosuite either. On the other hand, many third parties who made Sound Designer plug‑ins are porting their products over to Audiosuite, as are a number of TDM plug‑in manufacturers.

Functions included in the new software are:

• Normalising
• Pitch shift
• Time compression/expansion
• Sample‑level pencil‑point waveform editing
• DC offset removal
• Reverse
• Phase reverse
• Gain change
• Duplicate

In addition to Audiosuite, there are some major improvements in non‑destructive editing operations. You now have much more control over crossfades: fade‑out and fade‑in curves are independent of each other, and can be drawn manually. The crossfade can occur before, after, or surrounding the 'splice' point, and you can view what happens to the waveforms as a result of the fades before you execute them. It's also possible to audition a fade, though only through the Mac's audio hardware.

The Strip Silence feature, which decides where silences occur in a track and separates the track into regions accordingly, has likewise been improved, with separate on‑ and off‑threshold settings, minimum silence time, pre‑ and post‑roll (to make sure attacks and decays aren't cut off) and automatic sequential naming of the separated regions. You can select what you consider to be a silent region and, using the 'Identify Silence' command, tell the program to set the Strip parameters to recognise it as such.

MIDI, Quicktime & File Formats

Pro Tools' treatment of MIDI sequences has always been one of its weakest points: regardless of how complex your MIDI system was, it was only possible to choose either the Modem or Printer port to play back a MIDI track, whether it was recorded into Pro Tools directly or imported as a MIDI File from a sequencer. That has finally changed, and now, with OMS fully integrated into the software, a MIDI track can be routed to any instrument in your OMS Studio Setup. You can specify a MIDI channel or let the track play back on whatever channel it was recorded on originally.

If you've been jealous of MIDI + Audio sequencers that can play QuickTime movies along with music, or you lusted after Digi's old PostView software, which let you scrub picture with the audio, you'll be pleased that Pro Tools 4 lets you import a QuickTime movie and play it on the screen while locked to the audio, either in real time or scrubbed. You can't adjust the window size, but you can set the SMPTE offset of the movie. An extremely neat feature is that an imported movie shows up on its own track as a series of 'picons' (picture icons), which makes lining up audio events to video frames an actual joy. If the movie already has an audio track, you can import that too, either with the video or by itself. The software does not, however, recognise when a movie has a MIDI track.

Borrowing one of the best features of Digi's low‑end Session software, Pro Tools 4 also lets you export everything you've done — stereo audio and video — to a QuickTime movie, a process usually called 'flattening', but here referred to as 'Bounce to Movie'.

Besides QuickTime, a lot of other file formats are now supported, including WAV and SND, and you can work with files in a wide range of sampling rates and word lengths. Format conversion is automatic when you import a file. When exporting, you can down‑sample the session to 8‑bit resolution, using a proprietary 'Squeezer' algorithm that sounds pretty good. You can also change the sample rate, and there's a choice of five levels of conversion quality, from 'Low' to 'Tweak Head'. I experimented with all of the different settings and, oddly enough, found that the 'Low' setting provided the best‑sounding results — the others had lots of low‑frequency grunge in spots that were supposed to be silent.

Are We Having Fun?

If I told you that learning Pro Tools 4 was a breeze, and anybody could be up and running in no time, I'd be lying. This is a complex, sometimes daunting program that will cause a lot of beginners to lose a lot of hair. Most of the problem is simply that over the years Pro Tools has become more and more things to more and more people, and has achieved a level of complexity probably unsurpassed in the music and audio software world. There are programs out there that are far simpler to use — Audiovision, from Digidesign's parent company Avid, comes to mind — but they don't do anywhere near as much as Pro Tools now does. If you want this much power, you'll have to learn how to use it. Fortunately, with patience the software can be mastered, and seasoned users, once they get over the initial shock, will make sense out of it in a not‑unreasonable amount of time.

A big help is a whole set of new Macintosh key combinations that get you around quickly. The Option, Shift, Command and Control keys are all used liberally, singly and in combinations. For instance, if you're in Select mode the Control key turns the cursor into a scrubber, while the Control and Option keys together turn it into a very fast scrubber. Moving a fader while holding the Command key increases the resolution of the fader so you can adjust it in 0.1dB increments. Moving a fader that's in a group, while holding the Control key, temporarily releases it from the group so that you can trim an individual channel without disabling the group entirely. Playing with the key combinations for a while gives you the feeling that you're developing an intuitive understanding of the logic behind them, and you'll be able to stop constantly referring to the Quick Reference Card.

The screen does get very cluttered, however, and sometimes it resembles those old astigmatism tests where you were told to distinguish finer and finer lines on a grid. While I welcome the ability to set different track heights, when you mix up tracks in that way you can go cross‑eyed just trying to figure out what you're looking at. I would not recommend using the software on anything smaller than a 19‑inch screen, and if you can get a second monitor on line, even a small one just to deal with the mixer window, you'll be even better off.

One thing to note is that it's very easy to run out of DSP power in a single‑DSP Farm system. While it's true that buying processing tools in the form of software is cheaper than buying all the same tools as discrete pieces of gear (not to mention the fact that it keeps your studio cooler), there's a serious trade‑off: when you've got a rack full of individual boxes there's never any question about being able to use as many of them as you want simultaneously. In a PCI Pro Tools system, only three of the four DSP chips are actually available for plug‑ins (in NuBus systems only two are available), so once you've set up some compressors, some EQs and a single reverb, you've used up your DSPs. According to Digidesign, one DSP chip will allow you to load up to 12 compressors and up to 24 bands of EQ.

The solution is to buy extra DSP Farms, but they ain't cheap, and you need the computer slots to put them in. So, unless you have unlimited funds and expansion slots, you'll have to learn Digidesign's complex formulae for what you can use in conjunction with what else. The supplied Allocator software at least helps you to keep track of what's going on, but it doesn't change the fact that if you want to do a lot of processing you have to be prepared for a constant juggling act: setting up auxiliary buses, bouncing processed tracks, and doing off‑line processing with Audiosuite. If you have assigned a plug‑in to a track and then de‑assign it, the DSP it was using is not automatically freed up — you have to close and re‑open the session to do that.

I suppose I shouldn't complain — it still beats dealing with £100,000 worth of analogue gear — but it's important to realise that if you want to take advantage of all of the cool features Pro Tools offers (especially those mouth‑watering plug‑ins), you're going to have to put together a pretty large system.

Documentation

Not helping things as much as it could, unfortunately, is the documentation. I'm very sympathetic to the folks who wrote it — they had a gargantuan task on their hands — and they've produced an exhaustive and well‑organised manual, but it still is extremely tough going for the new user, and even a little intimidating to old hands. There is a 'What's New in 4.0' chapter for experienced users, and an excellent 'Essential Concepts' chapter, which is really required reading for all users, regardless of experience. Beyond that, however, the software cries out for a series of tutorials, which at least touch on all of the numerous parts of the program, but there are none. Like too many manuals, the emphasis is squarely on 'What does this do?', when what's really needed is 'How do I do this?' For instance, the concept of a 'comp' track, which seasoned Pro Tools users talk about all the time, is never once mentioned in the manual. If you have the patience to read and understand all the various manuals and Read Me files, you may have no trouble, but if you're the type who likes to dive in and explore a new program (and who isn't?), you're going to be doing a lot of floundering.

If ever a program called out for a spiral‑bound manual that could be left open on a flat surface, this is it. Digidesign used to use loose‑leaf notebooks, but unfortunately a few years ago they switched over to conventional bindings that require you to sacrifice a hand to keep them open, or else smoosh them down hard enough to break the binding and eventually cause the pages to fall out. And if you need to look up something in one of the auxiliary manuals while keeping your place in the main manual, you'll need three hands. (Where's that assistant?)

Conclusions

Minor complaints aside, Pro Tools 4 is great stuff. It does more than ever, better than ever, and faster than ever. Digidesign's engineers have thought a lot about how to make the new features accessible and logical, and while you may find yourself scratching your head from time to time and asking 'Why did they do that?', a little reflection and practice reveals that in most cases their decisions were good ones. With this release, Digidesign once again pull way ahead of the pack, and confirm Pro Tools' position as the most versatile, most bang‑for‑the‑buck, best‑supported digital audio workstation on the Macintosh, or any other platform.

And it's very clean — as I said before, I found only one minor bug in the program, and it literally never crashed. One can only assume that a major part of the five‑month period between Pro Tools 4's first announced shipping date and its actual release was spent bullet‑proofing.

Of course, this much power comes at a price, and it will take a while to get used to all the new tricks, take advantage of all the features, and fully assimilate what's under the bonnet, especially with all those Preferences to set. It's unfortunate that the documentation doesn't offer much in the way of hand‑holding, but at least (almost) all the information is there to be found.

There's another price, which I suppose could be called 'DSP lust'. With all the amazing third‑party add‑ons available, and more being announced almost daily, the prospect of putting together a super‑duper system that does everything you could ever want is highly tempting. But if you go for all the plug‑ins without also making a hefty investment in extra DSP Farms, you'll feel like a carpenter with a box full of fancy tools but only one hand.

Even at the lowly PowerMix level, however, Pro Tools 4 is one heck of an audio production program, and the more you add to it, the better it gets. If you can afford to indulge your lust, it can become a studio on your desktop with powers and abilities far beyond what anyone could have imagined would be found in a whole roomful of gear just a few years ago.