Apple Logic Pro 9 - Manual (Page 563)

2 Choose the desired settings in the Change Gain dialog:
• Set the required level change in the Change Relative fields by clicking the up or down
arrows in either field, or by directly typing values in either field. You can use the
percentage or decibel field to indicate the amount of increase or decrease you want.
• Click the Search Maximum button to search for the highest peak level. This automatically
sets a value that is used to alter the level of the audio file. The “Results in Absolute”
fields display the maximum level that will be achieved by changing the gain—by the
amount shown in the Change Relative fields.
3 Click Change to perform the gain change.
Important: You should never make a gain change that results in a value over 100%,
because this will result in digital clipping.
Normalizing Audio Files in the Sample Editor
Normalization is a process that raises the maximum level of a digital signal to a specified
amount—typically to its highest possible level without introducing distortion.
Tip: The start and end points for the section being normalized should generally not fall
within a continuous section of audio, as this will result in abrupt increases in volume after
normalization. The start and end points should therefore be located in sections that occur
just after, or before, musical gaps.
To normalize the selected area of an audio file
µ
Choose Functions > Normalize (or use the corresponding key command, default
assignment: Control-N).
Logic Pro locates the point with the highest volume in the selected area, and determines
how far this is from the maximum possible level. The level of the selected area is then
raised by this amount. The dynamic relationships of sample levels within the audio passage
remain unaltered.
563 Chapter 17 Editing Audio in the Sample Editor