Change the waveform amplitude scale
You can customize the waveform’s amplitude scale (plotted along the vertical axis), so that it’s displayed in percentage units or sample units.
Display the amplitude scale in percentage units
Choose View > Amplitude Percentage from the Audio File Editor menu bar.
Display the amplitude scale in sample units
Choose View > Amplitude Sample Value from the Audio File Editor menu bar.
Tip: You can also open the amplitude scale shortcut menu by Control-clicking the waveform amplitude scale itself.