Aftertouch is a basic concept for shaping performance expression and editing precision in DTM. You will run into it constantly in DAWs and MIDI gear. Beyond the name, understanding what it changes and what information it combines with makes it easier to work with.
What it does
Aftertouch lets you handle changes that notes alone cannot express, as well as relationships in time. Before making big changes to a setting, compare the dry sound with how it sits in the whole song.
Relationship to MIDI
MIDI expresses a performance by combining notes, velocity, control information, and more. Check what your current instrument and controller support, and use only the items you need.
Care when editing
Tidying values and curves too much can lose the natural variation of a performance. Edit only where necessary, and switch between before and after to listen. It is important not to judge from the shape on screen alone.
Where to start
Try the change on one instrument and one short phrase first. Once you can hear it, pull it back to the amount the song needs. Not moving several settings at once makes it easier to find the cause.
The basics of checking
Displays and names vary between DAWs and models. The fundamentals of the production environment and MIDI editing are covered in the DAW article.
