Published On: Thu, Jun 18th, 2009

Logic Tutorial: Transform Editing

Logic’s Transform window can significantly speed up the processes of editing and manipulating MIDI data. Mark Cousins shows you how to transform your workflow in this Logic Tutorial




Achieving the best results from any DAW requires a thorough exploration of all of its features, however appealing – or not! – they might appear at first glance. Certainly, Logic’s Transform window might not get the creative juices flowing as much as a new synthesizer plug-in, but underneath its somewhat austere front end are a set of tools that you can use to manipulate your music (as well as speed up your workflow) in ways that are impossible to achieve using conventional MIDI editors.

Whether you want to humanise a drum pattern, create complex random filter movements or just tighten up a performance, the Transform window offers a way of doing it.


Conditional Logic

Although MIDI data in Logic is stored as a series of numbers, we usually tend to deal with it using ‘graphical’ editing techniques – whether that’s moving notes around the piano roll editor, for example, or regions about the Arrange window. However, there are times when you will want to deal with the precise numerical values of MIDI, a process that’s probably best exemplified by the Event List Editor, which displays MIDI data as a list of values. This Event List is often the best tool for undertaking precision text-based editing – changing an audio region to have an exact length of 36 seconds, for example, or to move a group of notes by a few ticks.

Being text-based, the Transform window has strong conceptual links to the Event List, although in this example we’re using a technique called ‘conditional’ editing. Although it sounds complicated, conditional editing is easy to understand if you have a clear notion of what you want to achieve. For example, imagine you wanted to edit a MIDI part so that all notes below C3 are short 1/16th notes, each with a slightly different velocity. This would take a long time to achieve using the piano roll, requiring you to adjust the length and velocity of each individual note in the sequence. Conditional editing, however, enables you to specify both selection criteria (all notes below C3, for example), and processing instructions (fix length, randomise velocity). Logic will then perform the necessary edits on your behalf.

Human Behaviour

To help understand the Transform window, let’s see some of its most useful features in action. To open the Transform window, select the region(s) in question and choose Window>Transform. It’s also worth opening the Event List so that you can see the exact nature of the edits taking place.

Once the Transform window is open, select the Humanize option from the Presets dropdown menu in the top left-hand corner and click on Select and Operate to initiate the transformation. If you look closely, what you should notice is that Logic has applied a soft randomisation to the chosen sequence, adjusting the start positions of each note slightly as well as its velocity and duration. As with all of the Transform window presets, you can adjust the precise qualities of the effect (in this case, raising or lowering the amount of randomisation applied to the Position, Velocity and Length respectively).


Complete Transformation

Stepping through the remaining presets, it’s clear to see how the Transform window can offer a useful alternative to conventional editing techniques. One preset we regularly use is Fixed Note Length, which forces all notes to be of equal duration. This is a vital technique for creating sequencer-like lines from manually recorded material, making the notes appear as if they have been inputted in step time.

Of course, composers throughout the years have often used mathematical processes to manipulate and extend a simple musical motif. As well as the Half Speed and Double Speed presets, therefore, it’s interesting to try out the Reverse Position option as a means of flipping around the position of a sequence of notes – effectively creating a new melody or musical sequence from an existing phrase.

If you’re using the Reverse Position option it’s vital that you enter the appropriate duration that you intend the transformation to work over (from to, for example) so that Logic knows what material to reverse. Although unpredictable, Reverse Position is an interesting way of creating new musical material that you might never otherwise have thought of.

Natural Selection

You can also use the Transform window to create your own MIDI-based transformations. Let’s explore some transformations to the sequencer line, changing existing note data into pseudo-random controller data to modulate the filter cutoff on an ES2 patch.

Create a blank Transform set from the preset entitled **Create Initialized User Set!** and copy over the Touch Synth region to preserve the original note data. Now define the Select Event by Conditions section, establishing the information you want to process. In most cases this will simply involve changing the Status parameter so that it selects all MIDI data equal to (=) Note information.

Once  the selection criteria is established we can define the operations that need to be applied. Essentially, we’re applying mathematical functions to a segment of MIDI data – changing Note data to Controller data, for example, increasing all the velocities by 20 or randomising the pan settings.
If you click on one of the dropdown menus in the Operation on Selected Events area you should see a series of modifiers including Fix, Add, Flip, Mul and so on.
In this particular example we want to Fix the status to Control, Fix Data Byte 1 (currently labelled as Pitch, but actually, in this case, the controller number) to 1, then Randomize Data Byte 2. Clicking on the Select and Operate button in the lower right-hand corner initiates the transformation.

You will have noticed that Logic created two controller messages during the transformation process – one for the note start and another for the note end. Given that the note end messages have a Data Byte 2 value of 0 (you can see this in the Event List), we can use the Transform Editor to quickly delete these unwanted events. In this case, we need the selection criteria to focus on these specific events (set Status to be equal to Control and Data Byte 2 to be equal to 0), and you need only to click on the Select Only option to highlight the unwanted data, which can then be deleted using the [Backspace] key.

It’s also worth noting that you can re-assign the various components of the MIDI message using the black lines between the Selection and Operation areas. This feature makes it easy to ‘re-route’ pitch data, for example, so that it becomes a MIDI CC parameter level such as cutoff.

Environmental Impact

Although we’ve explored the transformation concept in the Arrange window, it’s worth remembering that the Transform window can effectively be inserted as an object in the Environment window.

To do this, open the Environment window and select the layer that you want to work on – Click & Ports is often a good choice, as this is the inward route for MIDI data entering Logic. The so-called Transformer object can be found under the New menu, and once it has been created you can patch the object straight into Logic’s MIDI signal path.

Double-clicking on the Transformer object will enable you to view its current status, both in respect to the Selection Criteria and any Operations that are being applied to the selected MIDI data. Although the controls aren’t as extensive as those in the main Transform window, you can still achieve practical transformations (reassigning certain controllers to better control a particular software synth, for example) or use the tools to create some more unexpected and unusual sounds. One of our favourite creative techniques is to reverse the keyboard position so that low notes become high and visa versa, but experiment with as many different configurations as you can.

MIDI Magic

Perseverance definitely pays off when you’re starting to understand and explore the Transform window. And although the Transform window’s relevance to your own productions and workflow might not be immediately apparent, you’ll soon come across a task that either becomes much less time-intensive through using the Transform window or simply can’t be achieved using any other modules or features in Logic.

As such, the Transform window really is the hidden gem as far as MIDI production in Logic in concerned, and once you’ve got to grips with it, you’ll regard it as a tool that you reach for on a daily basis.



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