User manual

AM700 Audio Measurement Set User Manual
4-81
FFT Analyzer
An audio signal is composed of many frequency components. Some of these
components can be due to undesirable effects of harmonic distortion or noise. Using
an oscilloscope to view the signal waveshape in the time domain does not permit
these unwanted frequency components to be distinguished from the desired audio
signal. The FFT Analyzer breaks the signal apart into its various frequency
components. When the result is viewed in a amplitude (y-axis) versus frequency
(x-axis) display, the distortion components and frequency-related noise components
are displayed as separate frequencies as shown in Figure 4-36.
Figure 4-36: FFT Analyzer measurement showing a dual channel spectral display