Mastering Your Tracks In Logic

Logic Notes

Published in SOS April 2003
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Technique : Logic Notes

A suitable order for the processing plug-ins when mastering in Logic.

This month's workshop shows you how to go about mastering your tracks in Logic, and there are also some useful tricks for faster audio and MIDI editing.

While there is no doubt that commercial record releases are best mastered by professionals, more and more people are mastering their home demos using products such as the TC Finalizer, the Drawmer DC2476 Masterflow and the Dbx Quantum. In the right hands, these units can produce excellent results, but what do you do if you don't have any mastering hardware, as might be the case if your studio is entirely software based? Perhaps the most obvious solution is to buy a software mastering package, such as the very powerful IK Multimedia T-Racks, but before you make another dent in your credit card it might be worth looking at your sequencer to see if the plug-ins that come with it can be used in a mastering application. As this article forms a part of Logic Notes, it will come as no surprise that my research was done using Logic v5, but the techniques and principles explored here are equally relevant to any other set of plug-ins that provide similar functionality. My aim was to put together a series of plug-ins to form an equivalent to what you'd expect to find in a hardware mastering processor and then to spend a while looking at how the various plug-ins might be used in a mastering context.

When using low threshold settings in Multipressor, it's safest to keep the compression ratios below 1.2:1.

Perhaps the most important element in any mastering processor is the multi-band compressor, for which I used the Multipressor. This goes right at the start of my processing chain. Multipressor defaults to four bands, but I usually reset it to three bands, which I think is easier to deal with for anyone new to multi-band processing. For mastering, I like to set the crossovers so that the majority of the mid-range sits in a single band, so I reset the low crossover point to around 150Hz and the high crossover point to around 5kHz. This makes it easy to determine what sounds each band affects — the low band mainly influences bass and kick-drum sounds, the high band covers anything with presence and sizzle, while the mid-band looks after everything else.

As a default position, I set the compression ratios to between 1.1:1 and 1.2:1 depending on the material. The more density you need, the higher you have to set the ratio in that particular band, but it's unwise to go much above

Current Versions     Mac OS X: Logic Audio Platinum v5.5 Mac OS 9: Logic Audio Platinum v5.5 PC: Logic Audio Platinum v5.5

1.2:1 in combination with the low threshold values used in mastering, which in this case I set at between -30 and -35dB in each of the three bands. This means that, instead of just the peaks being controlled, (as would be the case for the high-ratio, high-threshold setting used on individual tracks), the whole dynamic range of the signal is squeezed gently to produce a smoother, more dense overall sound — the default attack and release settings work fine for this. The gain reduction meters probably don't show more than 3-4dB of gain reduction on a typical mix, but that's usually enough to homogenise the various mix elements. You can also change the levels of the individual bands to effect a tonal change, but again it's best to stick to small changes of no more than two or three decibels. If you need more than that, use EQ.

Creative Selection Techniques     You can significantly speed up your MIDI editing chores in Logic by taking advantage of Logic's built-in data-selection shortcuts. These are accessed from various editor menus and many are also available as Key Commands. When using these shortcuts, keep in mind that most of them can be used to add data to the current selection by invoking them while holding down the Shift key. The bottom three sections of the local Edit menu in most of Logic's editors is the first place to look for data-selection shortcuts. (The Score window has an abbreviated set.) The first of these sections is for selecting objects based on their time position relative to Logic's Left and Right Locators or to already selected events. The other two sections offer selections based on object properties such as colour, channel, mute status, and so forth. Keep in mind that not all options work in all editors. For example, selecting by color is offered, but is non-functional (and doesn't make any sense) in the Event List window, where object colours are not displayed. Two other sources of selection shortcuts are the Note Events and Erase MIDI Events submenus of each editors' Functions menu. My favorites here are Select Top/Bottom Line for picking out the melody or bass line in a polyphonic sequence and Erase Unselected Within Selection for deleting events that I've manually deselected within a larger selection. When the built-in selection shortcuts don't do the job, consider creating a Transform preset in the Transform window, then using the window's Select Only button to select the objects. The Transform presets also appear on the Transform submenu of most editors' Functions menu, where they serve the purpose of opening the Transform window with the desired preset already selected. I find this especially useful for selecting MIDI events other than notes — all pan messages outside a certain range, for example. Len Sasso

For EQ I chose the Fat EQ, which comprises five bands, the middle three of which are peaking filters and the outer two shelving. In this example I've set the highest parametric band to around 15kHz with a Q of approximately 0.5 and applied a couple of decibels of boost to create the popular 'air EQ' curve that enhances detail without adding harshness. At the bass end, I've applied a little 76Hz boost to lift the kick drum sound, but balanced this using a gentle dip at 220Hz to stop the low-frequency

A little 15kHz boost using Fat EQ adds air to the sound, and some 76Hz boost can add weight, although it's worth balancing the latter with a cut at 220Hz to avoid lower mid-range coloration.

EQ affecting the lower mid-range. Naturally the actual setting depends on what your mix needs to make it sound properly balanced, but it is worth noting that most mastering EQ settings are quite gentle. This particular setting was devised to add life to a rather dull-sounding backing track.

The Exciter comes next in the chain, and though this might seem a rather odd thing to use in a serious mastering context, I like to think of it as an extension of EQ. Like its analogue counterparts, it generates new harmonics based on existing information, and when I first tried it I was impressed at how refined it could sound. Because the track I was working on was fundamentally dull, it would have required quite drastic high-end EQ to put it right, but I managed to combine more gentle EQ with a very moderate amount of HF enhancement to achieve what I feel was a better outcome. Note however that the default frequency setting when you open the Enhancer plug-in is rather too low to be subtle so I'd recommend moving this up to between 2.5kHz and 3kHz and then adding not more than 10 percent harmonics, as shown by the read-out beneath the Harmonics control.

The final link in the chain is always the limiter, and the Emagic Adaptive Limiter is ideal for this purpose, as it effectively limits and normalises at the same time. I set the target output level at -0.5dB to leave just a little safety headroom and then push the gain of an already 'close to peaking' signal up by between 3dB

The Exciter can often brighten a track much more effectively than EQ.

and 6dB to force the limiter into action. This increases the overall loudness of the track and shouldn't affect the sound significantly, but try to ensure that the limiter is only acting on signal peaks. If there's any sign of the mix sounding squashed or harsh, back off the amount of limiting.

Although the virtual mastering processor described here uses only Logic's own plug-ins, I've found that it is capable of producing extremely good results, provided that the material being processed doesn't require desperate measures. Every mastering engineer has their own set of secret techniques and approaches, but I believe that subtle adjustments are invariably best, especially if you are inexperienced in mastering. Also, as in any mastering situation, you need a monitoring system you can rely on. Double-checking using headphones is also a good way to track down distortions, which can occur if you don't take care with the gain settings to prevent clipping occurring within the signal chain. Individual plug-ins can be bypassed to check their contribution to the process and using a commercial recording as a benchmark reference is also good practice, as it's easy to lose perspective when you're processing a mix.

A Workaround For 'Replace' Edits     Logic is now so powerful that you can do a lot of serious audio editing inside it without having to involve an external editor. However, one feature every professional waveform editor has is plainly missing from Logic, so you have to engage a workaround. The missing feature is a 'replace' mode. On most other programs it works like this. Let's say you want to copy a kick drum beat and use it in place of one that was hit slightly late, or maybe in time but not hard enough. You'd copy the good beat, place the cursor where you wanted to copy the beat to, then you'd engage replace mode. The new beat would then be added to the audio file in place of whatever else originally started there, and the audio after the edit point would remain undisturbed. This is quite different to the normal paste command, which in Logic (if you simply place the cursor at the edit position) opens up a gap in the file to take the copied part, then moves everything after the edit along by the length of the pasted section. In a musical situation, this is clearly not what you want, even though it is right for most dialogue editing. The workaround is to note the length of the copied part by reading the 'number of samples display' at the top of the Sample Editor window when you highlight the section you want to copy. Then, when you select the place you want the replacement to start, use the cursor to select a length of audio after it that's exactly the same number of samples long as the original copied part. Now when you hit Paste, the copied section will replace what you've just selected and the audio after the edit won't be moved. Paul White