Analyzing and Fixing Problems in an Audio File

There are three steps in fixing problems in an audio file.

Stage 1: Analyzing an Audio File

When you analyze an audio file, you can select which types of analysis to perform.

To analyze an audio file
  1. In the File Editor, select the audio clip you want to analyze.

    Note: When analyzing an audio file in the File Editor, some analysis types might produce better results if you select a part of the audio file instead of the entire audio file. For more information, see Selecting All or Parts of an Audio File.

  2. Click the Analyze tab.

  3. In the Analysis Type list that appears, select the checkboxes next to the types of analysis you want to perform on the audio file.

    Figure. Analysis Type list showing the Parameter list, the Analyze button, and the Analysis Results.
  4. Click the disclosure triangle for the analysis types for which you want to set parameters (there is a disclosure triangle next to these).

    The Clicks and Pops and Silence analysis types have parameters you can set. Each type has a Threshold slider you can drag to set the threshold for detecting clicks and pops or detecting silence.

  5. In the Parameter list on the right, do one of the following:

    • Drag the Threshold slider left to lower the threshold or right to raise the threshold.

    • Type a value in the Threshold field.

    The Clicks and Pops Threshold slider uses an algorithm to detect transients that are clicks or pops. Moving the slider to the right results in fewer clicks or pops being detected.

    The Silence Threshold slider ranges from 0% to 10% of the full-scale level of the audio file, which corresponds to a range of -infinity dB to -20 dB.

    Figure. Analysis tab showing parameter list and Analyze button.
  6. When you’re ready to analyze the file, click the Analyze button, located below the Parameter list.

Stage 2: Viewing and Interpreting the Analysis Results

When you analyze an audio file, the problems detected through analysis are shown in the Results list in the bottom section of the Analyze tab.

Figure. Analysis Type list showing the Results list with a problem selected.

For each item, the following information appears in columns:

  • Status: Shows whether the problem is fixed or not fixed.
  • Problem: Shows the analysis type to which the problem belongs.
  • Start: Shows the point at which the problem begins.
  • Length: Shows the duration of the problem.
  • Ch: Shows whether the problem occurs in the left channel (L), the right channel (R), or both channels (LR) of a stereo audio file. If you analyze all or part of a monaural file, a dash (-) appears in the column.
To view analysis results
  • In the Results list, select one or more items.

    The part of the audio file to which the problem applies becomes red in the waveform display, making it easy to see where in the audio file the problem occurs. If you select multiple items, the parts of the audio file to which any of the selected problems apply become red.

    By default, the region shown in red in the waveform display includes some extra time before the first sample with the problem and some extra time after the last sample with the problem. This extra time is included so that when you play or loop the problem area, you can hear the problem in context.

If you want, you can narrow the problem area to include only the samples identified as having the problem, with no extra time.

To narrow the problem area to include only problem samples
  • Option-click the item in the Results list.

You can zoom in on an item in the Results list so you can see the problem area of the audio file closely.

To zoom in on an item in the Results list
  1. In the Results list, select an item.

  2. Do one of the following:

    • To zoom in and return to the regular display: Press and hold the Magnify button at the bottom of the Results list.

      The waveform display zooms in on the problem area for as long as you hold the Magnify button.

      Figure. File Editor showing a zoomed-in problem area highlighted.
    • To zoom in and stay at the new zoom level: Option-click the Magnify button at the bottom of the Results list.

Stage 3: Fixing Analyzed Problems

You can select items in the Results list and fix them individually, in groups, or all together.

To fix an item
  • Select the item in the Results list, then click the Fix button.

    The part of the waveform where the item occurs becomes red.

To fix multiple items
Do one of the following:
  • Shift-click to select contiguous items you want to fix.

  • Command-click to select noncontiguous items you want to fix.

You can also fix all items in a single operation.

To fix all items in one operation
  • Click the Fix All button.

Once you have fixed a problem, you can remove it from the Results list, so that you can focus on remaining problems.

To clear fixed items from the Results list
  • Click the Clear Fixed button.