Narration Processing Information

1. First step is to remove the pops and rushes of air that result typically from the ‘p’ sound.
   1. Open CoolEdit and listen to the wav for these sounds.
   2. Identify a pop sound(s). It will typically look like the peak in the following wav.

      

   3. Zoom into this peak. Use the mouse scroll wheel to zoom in / out.

      

   4. Highlight the peak, use a left mouse click to indicate the start of the highlight, and a right click to indicate the end. You want to highlight at points when the wav goes to zero (indicated by the red line).

      

   5. Hit delete to remove the unwanted noise.

      In some cases, you may need to use the command Generate->Insert Silence.. to restore the timing. Simply note the time length of the original selection (before the delete) and type that number in as the length of added silence.

2. Now you must normalize the wav. This is necessary to maintain a consistent volume regardless of the person speaking, mic used, etc.
   1. In CoolEdit, select Transform -> Amplitude -> Normalize. Then for ‘normalize to:’, enter 100%
   2. This is the result for the previous wav.

      

   3. The normalization value will depend on your voice, and how loud you generally talk. The idea is to not let too much of the wav go beyond the ‘boundary lines’ (these are indicated above), because this will result in a smaller signal to noise ratio (the boundary lines indicate where this ratio is optimal). Normalization values can range from 90% to 150% depending on the person speaking.
   4. The wavs often don’t appear this similar in amplitude. Below is a typical wav that has a greater variance. This was normalized to 120% because some parts were louder than others, and we are looking to get the majority of the wav to sit nicely between the boundary lines.

      

3. Listen to the wav again.
   1. If there more background hiss then usual, then the original wav was recorded at too low volume or was normalized too much.
   2. If there are pops from ‘p‘ sounds then repeat step 1.

• F2 repeats the last command (i.e. Normalize)
• F3 repeats the last command without the dialog box showing.