Controlling Noise and Removing Unwanted Audio

Welcome! The topic for this activity is: controlling noise and removing unwanted audio. Under this topic, we'll do three subtasks: reduce the master volume of the project, turn on the “noise gate”, and trim out unwanted parts of an audio track. And for this, we are using a GarageBand project with a single audio track.

Subtask 1: Reducing the Master Volume of the Project

First, we’re going to bring down the overall loudness - by reducing the master volume. To find the master volume slider, follow these steps:

  1. Go to the “control bar“, which is the first top-level element on your GarageBand window. Interact with the control bar by pressing control-option-shift-down arrow.
  2. Keep pressing control-option-right arrow until you reach the ”master volume” slider.
  3. Now, press control-option-shift-down arrow to interact with the slider, and press control-option-left arrow once - to reduce the master volume to 0db.
  4. We’ve completed the first subtask!

Subtask 2: Turning On the Noise Gate

For the second subtask, we’ll turn on the “noise gate” - which can be helpful to suppress background noise. To find the noise gate, follow these steps:

  1. Open the “item chooser” by pressing control-option-I. Use your keyboard to type the word “noise” to narrow down your options. From the remaining options, choose the “noise gate” item and press Enter.
  2. Now your VoiceOver cursor is on a text label, the actual noise gate checkbox will be on its left. So, press control-option-left once to find “noise gate controls”, which is currently unchecked.
  3. Press control-option-space once - to turn on the “noise gate”.
  4. We’ve completed the second subtask!

Subtask 3: Trimming Out Unwanted Parts of a Track

Finally, there will be times when neither controlling the volume nor turning on the noise gate will be enough to control noise. Then it might be helpful just to cut out the noisy part from your audio clip entirely. We have one track on this project, and we will remove everything after 4 seconds. To do that, follow these steps:

  1. Press E on your keyboard - where E is for Editor - to bring up the “Editor” group.
  2. You can use the comma key to move your playhead cursor to the left, or the dot key to move your playhead to the right. Use these keys to move the playhead to 4 seconds.
  3. Press command-T to split the track at 4 seconds.
  4. Now, press the Delete key to remove everything after 4 seconds.

Great! We’ve completed all the subtasks of this activity. Now you know how to control noise and remove unwanted audio. Goodbye!