Apply a measured change
- Select the part whose volume should change. Select the whole file for a global adjustment.
- Open Effects → Gain and adjust the percentage. Preview the change.
- Apply it and listen around the selection boundaries. Use Undo if the change sounds too strong.
Leave space for the peaks
Raising a signal too far can cause clipping. A file that is already distorted will not regain the original detail when made louder. Use smaller changes and check the loudest section.
Choose Gain or Normalize
Gain gives you direct control over the amount. Normalize calculates a level change from the highest peak. For a recording that swings between quiet and loud words, an envelope or compressor may help more.
Make a smooth transition
A sudden level change halfway through a sentence can be distracting. A volume envelope can raise or lower a phrase gradually.