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Automate Plug-in parameters
Published September 2001

To find out which MIDI message corresponds to a given plug‑in parameter, record some parameter changes and examine the resultant MIDI data in the Event List.To find out which MIDI message corresponds to a given plug‑in parameter, record some parameter changes and examine the resultant MIDI data in the Event List.

Advice on how to best automate your plug‑in parameters, as well as tips for lightening‑fast comping and a power‑user trick for simulating double‑tracking using Autotune.

One of the joys of working with Logic Audio is being able to make your audio faders dance up and down using MIDI automation. However, few people seem to take advantage Logic's automation for controlling their effects plug‑ins — a subject not really covered in any great detail in the manual. Automating effects is a powerful tool for mixing, and seeing that a number of plug‑ins are built into Logic, there has never been a better time to get automating.

Simple Effects Automation

Once you have worked out which MIDI Continuous Controller governs your plug‑in parameter, you can use Hyper Draw to edit it graphically.Once you have worked out which MIDI Continuous Controller governs your plug‑in parameter, you can use Hyper Draw to edit it graphically.

Assign a track for recording automation data by selecting A‑Playback (1‑16) from its instrument list. A‑Playback (1‑16) is an Environment object called a Channel Splitter, and cables together the first group of 16 Audio objects for automation purposes. If you look at your Audio objects on the environment page, you will notice that they are probably all cabled to one of these Channel Splitters, though each group uses the next letter of the alphabet — A‑Playback (1‑16), B‑Playback (17‑32), and so on. (Note that the Return Audio objects use a Channel Splitter called Bus Automation.) If you are using a large audio system there may be some Audio objects which still need to be connected to a Channel Splitter, a new one if necessary. Watch out when doing this, though, because an Audio object's cabling position often makes it look as if you've cabled to the object next door — the trick is to make sure that the appropriate fader highlights as you make the connection.

Now we are in a position to automate any of the controls on the first 16 Audio objects. For the sake of convenience, it helps to set up a screenset in which you can see both your Arrange window and your Audio object faders at the same time — I have screenset number nine permanently set up for this purpose on my system. Select your automation track, go to your appropriate screenset, start recording, and then move any of the first 16 audio faders up and down. Your movements will be recorded as MIDI Continuous Controller messages. When you've finished recording, and play back again from the beginning of your song, these MIDI messages will cause the faders to move as you recorded them.

It is possible to achieve exactly the same automation with any of your plug‑in effects, regardless of which variety or type they are. For the sake of demonstration, select the Fat EQ plug‑in as an Insert effect on one of the first 16 Audio objects, and then open up its editor window. Just as before, you can record real‑time tweaks to any of the plug‑in's controls on the A‑Playback (1‑16) automation track. For the sake of demonstration, record yourself moving the centre Gain control. When you play back the automation recording from the beginning of your song you will see the control moving, not to mention a rather nice moving graphic!

Tracking Down MIDI Controller Numbers

If you can't get a good enough result when using Logic's real‑time crossfades to disguise an edit point, give the Sample Editor's audio‑processing functions a go as well.If you can't get a good enough result when using Logic's real‑time crossfades to disguise an edit point, give the Sample Editor's audio‑processing functions a go as well.

If you haven't discovered so already, you may notice that the mouse can be rather cumbersome for manipulating controls for automation. The biggest minus point is the fact that your movements are exaggerated, and it is rather difficult to achieve a perfect sweep or fade in this way. Therefore it's usually better to enter automation data in a more accurate way.

In order to do this for the data we just recorded from our Fat EQ plug‑in, we need to find out which MIDI Continuous Controller the centre Gain control employs. Highlight the relevant recorded object on your automation track and open the Event List from the Windows menu. This will show the movements you have made as event numerics. In the Num column you should have a number which is repeated several times — 77 in the case of Fat EQ's Gain control. Armed with this number, we can use any of the other editors available in Logic to manipulate this value.

Automating With Hyper Draw

A particular favourite of mine in these instances is the Hyper Draw editor which allows you to send automation data directly to specific Audio objects, by drawing lines onto your audio regions, rather than having to work with a separate automation track. Highlight the track to which your first Audio object is assigned in the Arrange window, and select Other from the HyperDraw submenu of the View menu. You will be invited to type in a MIDI Continuous Controller number, so you should enter 77 in this case.

As seasoned users of Hyper Draw will know, the editor is not apparent until you zoom in quite far vertically, at which point the object should display a coloured area with '77' written in the top left‑hand corner. Now you can use the Hyper Draw facility to create a perfectly smooth gain change for your Fat EQ control by clicking and dragging in this coloured area — the gain will follow the contour of the line that you've drawn on the object. The beauty is that you can do this over and over again, putting several controller functions onto one track object. The only downside is that you have to do this one controller at a time — if you want to have an overview of a number of controller parameters, then you'll need to use the Hyper Edit window, which is a whole new subject in itself. Dave Gale

Logic Tips

If you were one of those people who long since gave up on Logic's internal metronome because of it's annoying pinging sound, then you owe it to yourself to give it another try. As of v4.7, Emagic have replaced it with a proper metronome click. About time too! Dave Gale

If you're starting out with using virtual instruments in Logic (VST or Logic's own), you may notice that you sometimes can't hear the instrument sounding when clicking on notes in one of the MIDI editor windows. This is because virtual instruments behave slightly differently from hardware MIDI instruments. To ensure that you can always hear the instrument, just make sure that the track relating to that sequence is selected in the Arrange window. Paul White

If you hold down the Mac's Control key (Alt key on the PC), the pointer turns into the square Magnifying Glass tool whenever you click the mouse button. Use this to 'box in' any Arrange window object you wish to magnify, and when you release the mouse button that object will blow up to fill the screen. Click anywhere on the window background to return to your previous zoom resolution. Paul White

Fancy moving a plug‑in to a different audio object? Open up the Audio Configuration window from the main Audio menu and use its Hand tool to simply drag and drop the plug‑ins into their new locations. Mike Senior

Artificial Double‑tracking Using Autotune

Double‑tracking is a classic way to thicken vocal lines, but not all singers are capable of repeating a performance with the necessary degree of accuracy. On the other hand, there are lots of delay and chorus treatments that allow you to fake it, but let's face it — it sounds faked. Nevertheless, there is a way to emulate double‑tracking from a single vocal part within Logic that sounds surprisingly real. The secret is in the creative abuse of one of Antares' range of VST Autotune plug‑ins.

Step one is to copy your recorded vocal part onto an adjacent free audio track. Next, insert Autotune into the copied part's track and dial in the correct scale notes for the part being treated. Follow the normal procedure (as outlined in the Autotune manual) for optimal, natural pitch correction, checking the part in isolation using the Solo function to ensure that it sounds clean and that no notes are being forced to the wrong pitches.

Now, play back the original track and the pitch‑corrected copy together. Unless the singer was unnaturally accurate in the first place, you should notice a doubling effect as the corrected version runs alongside the original version. However, unlike using a pitch shifter, the pitch differences between the two audio parts will be related to the vocal performance, so they'll vary from note to note. In effect, you have natural pitching running alongside Autotune's improved pitching.

Match the levels and you should hear a convincing double‑tracking effect, though this can be further enhanced by delaying the corrected track by between 10 and 40 milliseconds relative to the original. If you need an even thicker vocal part, make two copy tracks and apply Autotune to them both with different pitch‑correction speed settings. This will introduce further pitching differences that will add to the layered vocal sound. Paul White

More Advice On Comping

I've recently been trying out Paul Farrer's suggestions about comping (see March 2001's column), and I've come across some useful additional tips which I thought would be worth sharing. For a start, don't necessarily give up on a particular edit because you can't make it work using the real‑time crossfading. I found that I could get difficult edits to work by combining a real‑time crossfade with tweaks to the audio files themselves using the Sample Editor's Function menu. Usually these were only Change Gain operations, to even out levels between the crossfaded sections, but I sometimes had to resort to applying Fade In, Fade Out and Silence commands in order to prevent an unwanted element of one of the files breaking through during the crossfade. It's worth experimenting here, and you can do this with impunity as long as you don't close the Sample Editor and make the edits permanent. Even so, I'd suggest working on a copy of the audio region to be edited, in case you change your mind. Highlight the section of the audio file you want to process (leaving yourself a little margin for error) and select Save Selection from the Audio File menu — this will be easier on your storage space that saving a backup of the complete take when prompted to by Logic.

Another thing I've noticed is that it's very easy when comping in Logic to lose objectivity about how natural your editing sounds. It's quite easy to convince yourself that an edit sounds natural, only to discover that it sticks out a mile when listening back to it later. For this reason, listen through to your track every now and again without watching the audio regions go by — simply look away, or move to a screen set without the Arrange window displayed. And speaking of screen sets, Ab Wilson's trick of having two linked Arrange windows open (one zoomed out for overview, one zoomed in for detail — see February 2001's column) is great for navigating around during comping. However, I found it best to make the lower window a floating one, as this ensures that all key commands used during editing apply only to the upper window.

Finally, there are a couple of key commands which I find really useful when comping: Play Selection is handy when tweaking the crossfades, while Tie Objects By Length Change quickly removes any untidy gaps or overlaps between adjacent regions. Mike Senior

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