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Logical Edit Function: Part 1

Steinberg Cubase Tips & Techniques By Paul Sellars
Published December 2000

This month's Cubase tips column focuses on one of the sequencer's most powerful but under‑used features, the Logical Edit function. Paul Sellars begins a two‑part explanation of its operation.

Unlike the other Edit windows in Cubase, Logical Edit is quite difficult to learn by trial and error, and its intimidating appearance doubtless discourages some users from learning to use it at all. Over the next two issues, Cubase Notes will provide a basic introduction to Logical Edit, which will hopefully inspire you to explore its potential as both a labour‑saving device and a useful compositional tool.

The Basics

In earlier versions of Cubase, Logical Edit can be opened from the Edit menu, while in later versions it appears on the Functions menu. In all versions, the keyboard shortcut is Ctrl+L (Windows, Atari) or Command+L (Mac OS). When you select a Part and open the Logical Edit Window you should see something like Screen 1, below. By default, the Logical Editor opens in Expert mode. If you click on the button marked 'Easy' it switches to Easy mode (see Screen 2 (note that in very early Atari versions of Cubase, Logical Edit was laid out differently).

Logical Edit works in exactly the same way in Easy mode as it does in Expert mode, but has fewer options. It's a good idea to learn the basic concepts of Logical Edit in Easy mode, and then move on to Expert mode when you're ready to take advantage of the more advanced editing options.

Like Score Edit, Key Edit, Drum Edit and List Edit, Logical Edit can work on either Drum or MIDI tracks, and (like List Edit) can also be used to edit Mixermap events on Mix tracks. However, Logical Edit is different from the other Edit windows in that (to quote from my manual) "...it allows you to make changes to your music based on logical or mathematical criteria, rather than musical." To put it another way, Logical Edit allows you to alter notes and other MIDI events in a Part or Track systematically, according to a 'rule' or 'rules' that you define.

Imagine, for example, that you wanted to tell Cubase to delete all notes with a velocity value of less than 100 from a particular Part. Screen 3 shows how the Logical Editor (in Easy mode) could be set up to express this rule. Clicking on 'Do it' ('Perform' in some versions of Cubase) would delete the desired notes from the selected Part — or, if no Parts are selected, all Parts on the active Track.

While Logical Edit might seem puzzling at first, it is actually very easy to set up edits once you have familiarised yourself with the layout of the window. Look again at Screen 2. You'll see that the window is roughly divided into three rows, with Filter options on the top row, Processing options on the second row, and with Presets and Functions options on the bottom row. To set up an edit, you simply work from left to right and top to bottom, setting each required option as you go.

<h3>Opening Up The Filter</h3>

The Filter stage is used to select what data will be affected by your edits, and the Processing and Functions stages allow you to control exactly how it will be affected. The Presets section allows you to store useful settings for easy recall (presets can actually be accessed from the Logical submenu of the Functions menu without having to open the Logical Edit window at all).

Starting in the Filter stage, in the top left‑hand corner of the Logical Edit Window, the first option to set is the uppermost drop‑down menu in the Event Type column. This has three possible settings (known as Operators); Ignore, Equal and Unequal.

  • Ignore (which, in earlier versions of Cubase, was labelled 'All') instructs Logical Edit to allow all MIDI messages to pass through the Filter, regardless of their type.
  • Equal instructs Logical Edit to only allow MIDI messages of the type specified in the lower drop‑down menu in the Event Type column to pass through the Filter.
  • Unequal instructs Logical Edit to allow all messages apart from those of the type specified in the lower drop‑down menu in the Event Type column to pass through the Filter.

The setting of the lower Event Type drop‑down menu determines what meaning the Value 1 and Value 2 settings will have, as listed in Table 1 below.

After Value 1 and Value 2, the final option in the Filter stage is Channel, which refers to the MIDI channel number that is stored with each event, ie. the MIDI channel on which each event was originally sent. This, of course, might not be the same as the MIDI channel that is set for the Part or Track.

In addition to Ignore, Equal and Unequal, the Channel option can also be set to use the following Operators:

  • Higher allows only events with a value higher than that set in the field below the drop‑down menu to pass through the Filter.
  • Lower allows only events with a value lower than that set in the field below the drop‑down menu to pass through the Filter.
  • Inside allows only events with a value that falls between the values set in the upper and lower fields below the drop‑down menu to pass through the Filter.
  • Outside allows only events with a value that does not fall between the values set in the upper and lower fields below the drop‑down menu to pass through the Filter.

By setting the right combination of Operators you can control precisely which data is allowed through the Filter and which is not. Data that is allowed through the Filter will be affected by the edits you set up. Data that is not allowed through the Filter will be left unchanged.

Filters And Functions

As you will see, it is possible to perform a variety of simple edits just by setting up the Filter and choosing an appropriate Function from the drop‑down menu(s) in the Function stage — and without setting up anything in the Processing stage at all. Our first example worked in exactly this way: the Filter was set up to allow through only Note events with a velocity (Value 2, when Note is the selected Event Type — see Table 1 again) of less than 100, and Delete was selected in the Function drop‑down menu.

To perform other simple edits, the Function menu can be set to any of the following:

  • Quantize, which quantises note events passing through the Filter to the set in the Quantize Value menu (immediately beneath the Function menu).
  • Extract, which cuts the Filtered MIDI data from a Part and pastes it into a new Part on a new Track. (This option is only available if you enter Logical Edit from the Arrange window, rather than from another Edit window.)
  • Copy, which works in the same way as Extract, except that it copies and pastes the Filtered data instead of cutting and pasting it.
  • Delete, which deletes the Filtered data, as we saw in our first example.
  • Select, which selects the Filtered MIDI, so that it can be edited using any of the normal functions available in any of the other Edit windows. (This option is only available if you enter Logical Edit from one of the other Edit windows.)

Screens 4 and 5, above, show two more examples of what can be done using just Filter and Function settings. In Screen 4, all notes in the selected Part between (Inside) C3 and F3 (note numbers 60 to 65) with a velocity greater (Higher') than 25 are selected (using the Select option on the Function menu). The MIDI data is not altered in any way; it is merely selected, so that it can be edited using any of the normal editing functions in another Edit window. In Screen 5, all notes between F3 and A#3 (note numbers 65 to 70) with velocities between (Inside) 30 and 95 are cut and pasted (Extracted) to a new Part on a new Track (you may need to create a new track, set to the appropriate MIDI channel, for this to work). Try experimenting with different settings in the 'Filter' and 'Function' stages to see what other effects can be achieved.

Next month, I'll consider some of the more complex editing possibilities offered by the Processing stage, and work through some examples demonstrating the extra Operators available in Expert mode. See you then...

Naming Multiple Parts

If you're anything like me (and if you are, I sympathise), you'll find that an element that starts life in your track as one thing often ends up getting warped to the point where it effectively becomes something else. A bit of experimental pitch‑shifting here, a little over‑enthusiastic filter modulation there, and suddenly what you thought was a bass line has turned into some kind of burbling high‑pitched synth. This is all well and good — the creative process is often strange — but what do you do with the 40 or so copies of the original Part, all of which are now misleadingly labelled 'Bass'? Do you spend 20 minutes renaming each one individually? No. Instead, hold down Alt and double‑click on just one of the offending Parts. This will open the Part name dialogue box as normal. Now enter the desired new name and hold down Ctrl (Windows), Option (Mac), or Alt (Atari) while pressing Return. All Parts on the track will be automatically given the new name.

 

Event Type Value 1 Value 2
Note Pitch (note number) Velocity
Poly‑Press Pitch (note number) Amount of pressure
CtrlChange Controller number Amount of change
ProgChange Program number (Not applicable)
Aftertouch Amount of pressure (Not applicable)
Pitch‑Bend Fine bend value Coarse bend value

Copying Multiple Parts

When arranging a Song you will almost inevitably want to copy and paste the various Parts that make up your verses and choruses. This involves first selecting the Parts you wish to copy to the clipboard. There are several ways to make multiple Part selections in an Arrange window: you can click on a Part and then Shift‑click on subsequent Parts, you can click in empty space and drag a rectangular selection to cover the desired Parts, or you can double‑click in a gap between two Parts on the same Track to select all the Parts on that Track. Probably the most convenient way to select multiple parts, however, is to move the Left and Right Locators to either side of the desired Parts, and then choose Copy Locator Range (Copy Range in some versions) from the Structure menu. You can then paste copies of these Parts wherever they are needed.

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