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Logic Pro Setup Guide

How to use VEX MIDI EXPRESSION in Logic Pro to transform your MIDI controller data.

Native MIDI FX Support

Good news! Logic Pro has native support for third-party MIDI FX plugins. VEX appears directly in Logic's MIDI FX slot and can be placed before instruments on the same track. No complex MIDI routing required!

How It Works

In Logic Pro, software instrument tracks have a MIDI FX slot above the instrument slot. MIDI flows through these slots in order:

MIDI Input → [MIDI FX Slot] → [Instrument Slot] → [Audio FX] → Output

VEX sits in the MIDI FX slot, transforming your MIDI data before it reaches the instrument.

Setup Guide

Step 1: Create a Software Instrument Track

  1. Go to Track → New Software Instrument Track (or press Option+Cmd+S)
  2. Choose an instrument (e.g., Alchemy, Retro Synth, or any third-party synth)
  3. Click Create

Step 2: Insert VEX in the MIDI FX Slot

  1. Look at the Channel Strip on the left side (or in the Mixer)
  2. Find the MIDI FX slot - it's located above the Instrument slot
  3. Click on the MIDI FX slot
  4. Navigate to: AU MIDI-controlled Effects → Extrasensory → VEX MIDI EXPRESSION
  5. Click to insert VEX

Your channel strip should now show:

[MIDI FX: VEX MIDI EXPRESSION]
         |
         v
[Instrument: Your Synth]
         |
         v
[Audio FX slots...]

Step 3: Configure VEX

  1. Double-click the VEX slot to open the plugin window
  2. Add a mapping for your CC number:
    • Click + Add Mapping
    • Set the CC number (e.g., CC1 for Mod Wheel, CC74 for Filter)
    • Choose a transform type (Bouncy, Spring, Warp, etc.)
  3. Move your MIDI controller to verify input is received

Step 4: Play!

  1. Make sure your MIDI controller is connected and selected in Logic's preferences
  2. Record-enable the track (press R on the track header)
  3. Play your MIDI controller - the instrument receives transformed MIDI data!

Stacking Multiple MIDI FX

Logic Pro allows you to stack multiple MIDI FX plugins:

  1. Hover over the top or bottom edge of an existing MIDI FX slot
  2. When you see a green line, click to insert another MIDI FX slot
  3. Insert additional VEX instances or other MIDI FX plugins

MIDI flows through them in order from top to bottom.

MIDI CC Mapping in Instruments

After VEX transforms your CC data, you need to map it to instrument parameters:

Logic Pro Instruments (Alchemy, Retro Synth, etc.)

Most Logic instruments respond to standard MIDI CCs automatically:

  • CC1 (Mod Wheel) - Often mapped to vibrato or filter
  • CC74 - Brightness/Filter cutoff
  • CC71 - Resonance

Third-Party Instruments

Most synths have built-in MIDI Learn: right-click the parameter → "MIDI Learn", then move your controller through VEX.

Troubleshooting

VEX doesn't appear in MIDI FX menu

  • Ensure VEX is installed in /Library/Audio/Plug-Ins/Components/
  • Go to Logic Pro → Preferences → Plug-in Manager
  • Click Reset & Rescan Selection to rescan Audio Units
  • Make sure VEX is not disabled in the plugin list

VEX doesn't receive MIDI input

  • Check that your MIDI controller is selected in Logic Pro → Preferences → MIDI
  • Ensure the track is record-enabled (R button)
  • Verify your controller is sending the correct CC number

Plugin validation failed

  1. Go to Logic Pro → Preferences → Plug-in Manager
  2. Find VEX in the list
  3. Select it and click Reset & Rescan Selection
  4. If issues persist, try removing and reinstalling the plugin

Recording Transformed MIDI

When you record MIDI in Logic with VEX in the MIDI FX slot:

  • The recorded MIDI will be the original, untransformed data
  • VEX transforms it in real-time during playback
  • This lets you adjust VEX parameters after recording without re-recording

Need help? Contact us at support@extrasensory.studio