Using a spectrum graph
In the spectrum graph, the horizontal axis represents frequency in Hertz (Hz), while the vertical axis represents amplitude in decibels (dB).
Displaying a spectrum graph
1.Open an audio file.
2.Select the portion of the waveform you want to analyze. The sound or note you want to analyze should be in the center of the highlighted area.
Note: Analyzing long sections of audio can take a long time and decreases the time resolution, so your selection should be relatively short. Also, if the audio has a low amplitude level, you can boost it by using the Volume or Normalize functions. For more information, see Volume on page 193 and Normalize on page 186.
3.From the View menu, choose Spectrum Analysis. The Spectrum Analysis window is displayed.
4.Use the toolbar at the top of the window to set your display options.
Tip: You can also click the Settings button (
) in the Spectrum Analysis window to set additional options.
The spectrum graph displays the amplitude (in dB) of each frequency component from 0 Hz (DC) to the Nyquist frequency. Frequency is displayed along the X (horizontal) axis, and the amplitude is displayed along the Y (vertical) axis.
Tip: You can continue to make selections in the sound file with the Spectrum Analysis window open (just move the cursor or make
selections as you normally would). Click the Refresh button (
) in the Spectrum Analysis toolbar to update the display. If no selection is made, analysis is performed on the samples immediately following the cursor position.
280 CHAPTER 19