IK Multimedia T-racks

T‑Racks's three elements aim to simulate an analogue mastering EQ, compressor and multi‑band limiter.

Paul White tries desktop mastering using the new all‑in‑one PC or Mac package from IK Multimedia.

Hardware mastering boxes seem to have been the fashion recently, but it's also possible to do mastering using only software, and if you don't need every conceivable bell and whistle, this can be a very cost‑effective alternative. The T‑Racks mastering software under scrutiny here originates from a small company in Italy, and they've been considerate enough to make versions that will run on both Mac and PC platforms. The minimum Mac requirement is a 180MHz PPC603e or a 120MHz PPC 604e, though a G3 is ideal. Likewise, the PC user can get away with a 200MHz MMX (only) PC running Windows 95 or 98, though a Pentium II is recommended, in which case Windows NT 4.0 can be added to the list of supported operating systems. IK Multimedia are also reported to have a working BeOS version. In most cases, at least 32Mb of memory are needed, though Pentium II owners should have at least double this figure. A CPU activity monitor is provided as part of the program, so you can see how close you are to pushing your computer over.

The software comes on CD‑ROM, and Mac users get a dongle similar to the ones used by Waves that connect in series with the keyboard. The manual mentions that USB dongles are also supported. You also have to enter the serial number of the software when installing it — I would have thought dongle protection was enough! Installing is simply a matter of clicking Install and entering the serial number when prompted.

Some means of getting digital audio into and out of your computer is needed as T‑Racks works on existing files. It doesn't handle recording or the processing of an audio input in real time, so it's realistic to expect that you'll be using it with some other stereo editing or recording program. A means of monitoring the audio to a high quality is also recommended; in the case of the Mac, any Sound Manager‑compatible audio output is usable and may be selected under Sound in Control Panels. Only 16‑bit audio files are supported — WAV‑format for PCs, and both AIFF and SDII files for Macs. Sample rates of 32 to 48kHz are supported, though 44.1kHz is recommended for CD mastering.

What Does It Do?

Perhaps brushed aluminium fits in better with your studio's Feng Shui...? T‑Racks offers a choice of colour schemes for its virtual modules; this shot also shows the master output level meter, CPU usage meter and snapshot toolbar.

T‑Racks isn't an editor — it is intended to process existing audio files using 32‑bit, floating‑point algorithms designed to emulate analogue compression, equalisation and multi‑band limiting. It can also handle fade‑ins/outs and apply soft or hard saturation, and it dithers the audio after processing to maintain optimum low‑level resolution. The various processing blocks, which are represented on screen as bright yellow rack modules, use a form of analogue modelling which, the designers claim, can reproduce the audio quality and character of high‑end analogue hardware processors.

The user interface is entirely graphical, with click‑to‑operate switches and drag‑to‑turn knobs; if you don't like the colour, you can open the preferences and opt for copper or chrome panel finishes instead! I must admit that when I first saw the choice of gold, copper or chrome interface material, I thought the designers had gone to the lengths of modelling the effects of the audio connector plating, but happily they're rather more rational than that! There's a limited amount of on‑screen help that describes the functions of the controls as the mouse is used to point at them.

A row of virtual glowing valves pulsates along the top of the screen, purely for visual effect. However, the usual operating system menu bar is conspicuously absent (instead, the program has its own at the bottom of the screen), which can be frustrating when you want to leave the application to look for something else — the only way I could find to do this was to quit the program, but at least reloading it is very fast.

To open files for processing (which can be in mono or stereo), you use the Open button at the bottom left‑hand corner of the screen. There is only one main screen, which, as you can see, is presented as three virtual rack units with the addition of transport controls to play back the selected file as you're tweaking the controls. Audio files may be looped in playback, so you don't have to keep restarting short files as you set up the processors, and the usual fast wind buttons actually jump to the next or previous markers, if you've inserted any. Up to eight draggable markers can be inserted by pressing Mark at the appropriate time; to erase a marker, just drag it off the left‑hand side of the file progress bar. A go‑to‑start button is included along with Start, Stop and Loop buttons, and the loop length may be changed by dragging the loop markers so as to play only a part of the file. A draggable slider follows the file's progress, so you can also use this to move around quickly if you need to. There is an audio buffer that can be adjusted via the Preferences section if playback becomes glitchy, but I had no problems using the default setting.

At the top of the virtual rack is a quasi‑parametric equaliser featuring variable‑frequency 24dB/octave high and low‑cut filters (extremely useful), two more conventional high and low‑pass shelving filters with variable frequency and gain, and two mid‑range band‑pass filters with variable frequency and gain plus switchable low or high Q. The manual wrongly claims that this constitutes a 6‑band parametric EQ, but it's still plenty powerful enough for most jobs, and sounds very analogue. Each of the processing sections has its own bypass button as well as a Reset All switch to bring up the neutral settings. Patch buttons can switch the EQ before or after the compressor, which is a nice touch, and as you'd expect, the limiter always stays at the end of the chain.

In general, the EQ range is impressive with up to 15dB of cut or boost. I was a little disappointed that the shelving EQs couldn't be switched to band‑pass mode and that the Hi frequency could only go up to 8.5kHz, but the upper mid can be swept all the way up to 18kHz — which is useful if you need to add a wide‑band gloss in the 15kHz range. A graphic display of the EQ response curve is shown as part of the filter module.

The compressor has a soft‑knee characteristic, so the degree of compression is dictated by how far you advance the Input Drive knob, and the amount of gain reduction is displayed on a (virtual) vintage‑style moving‑coil GR meter. Both attack and release times are fully variable, though there's no auto setting. A stereo enhance control is also provided to increase or reduce the apparent stereo width: by the same token, a balance control is provided in the Output stage to compensate for any left/right level imbalances.

Limiting is carried out in a separate section to the compressor via a dedicated three‑band limiter equipped with Input Drive, Release Time and Overload controls. The benefit of multi‑band limiting is that more gain reduction can usually be applied before audible side‑effects are evident. The same style of gain‑reduction meter is used as in the compressor. The Overload control determines how long the limiter is allowed to clip before gain reduction occurs: the rationale for this is that as very short periods of clipping are inaudible, you may decide to let them through in exchange for a slightly higher level than you would get if you tried to limit every peak that came along. The three bands are preset and are invisible to the user.

The Output stage comprises an output Level control, basic stereo metering with clip lights, and the Balance control mentioned earlier. If you want more accurate metering, pressing Meter on the menu bar at the bottom of the screen brings up a long vertical bargraph output‑level meter. In addition to the Bypass switch, there's another switch for setting hard or soft saturation. In hard mode, the signal is permitted to clip if the gain is set too high, whereas in the soft mode, clipped signals tend to be rounded off more progressively, rather like tube or tape saturation.

Using T‑Racks

The manual is mercifully brief and the user interface is almost entirely intuitive, though the manual could do more (or even anything at all!) to explain how to use your soundcard to monitor what's going on. I reviewed the Mac version and discovered via the T‑Racks web site's FAQ section that Apple users select their output using MIDI Manager. Since my Mac has a Digidesign Pro Tools system installed, I chose to use this as my monitor output as the quality is extremely high, allowing critical evaluation of the processing. I was impressed by the smooth, musical sound of the various modules, and though multi‑band compression might be better suited to mastering than the single‑band variety, the facilities provided here work surprisingly well considering the low cost of the package. The compressor has a very warm, easy‑going sound that doesn't pump noticeably unless you really hit it hard, whereas the limiter pumps quite musically once you push it past the level at which it can control peaks invisibly.

I liked the sound of the equaliser, and even though it isn't fully parametric, it is ideally suited to fine‑tuning a master recording. It sounds more like an analogue EQ than most digital equalisers I've tried — and a good‑quality analogue EQ, at that. Having more range on the upper mid than on the HF filter is a bit odd, but I had no problems getting the results I wanted. Similarly, the limiter will let you squash the signal by several dBs without wrecking the sound, though going much beyond 4 or 5dB of peak limiting is probably pushing things unless you're deliberately after a pumped‑up sound. You also need to be gentle with the soft saturation mode — it's quite smooth if used sparingly but the sound becomes noticeably distorted if you lay it on too heavily.

Having stereo width control and a balance control is sensible in any mastering processor, as is the ability to do fades in and out, though I would have liked the option to trigger the fades manually. In fact, the only problem I encountered was when the Mac went into energy‑saving sleep mode. I found that if T‑Racks was running, I couldn't wake it up again! I'm not sure if this is some peculiarity of my system or not, but I feel it's worth mentioning.

Once you've auditioned the processing in real time, you still need to write a processed version of the file back to your hard drive, and this can be done either in real time or off‑line. On my G3 266, the off‑line processing ran significantly faster than real time, but if you need to make changes as the file is being written, such as adjusting controls or calling up snapshots, you must write the file in real time so you can hear it play as it writes. Which option you use is selected in the Preferences section along with dithering on/off, audio buffer size and the interface colour.

Summary

T‑Racks has its minor irritations and limitations, such as the lack of a traditional menu bar, and the fact that it can't be used from within other applications, but it is very easy to use, it isn't expensive and it sounds pretty much as good as it claims to. It isn't as flexible as a truly multi‑band unit, but having a three‑band limiter certainly helps, and both the compressor and equaliser have a warm, musical sound that's kind to most mixes. The multi‑band limiter can also be used to increase the overall loudness of a file significantly without introducing obvious side effects, unless you want them for creative reasons.

T‑Racks is well thought‑out for general mix sweetening, and of course, there's no reason not to use it to polish up tracks you've recorded in your audio sequencer prior to mixing if you want to. I feel that the interface is approachable enough to help you get the best out of your mixes, even if you're relatively new to signal processing. This is a very worthwhile product from a new name in signal processing, and I'll be watching carefully to see where they go next.