The Perfect System; Measurement Methods - PROEL AXIOM - VERSION 2.0 Manual

B.2. THE PERFECT SYSTEM
B.2 The Perfect System
For a system to be perfect or, rather, for it to be free of linear distortion, theoretically it must have a flat
mode response (in the band of interest) and a linear phase response (if visualized on a linear frequency
scale).
The inclination of the phase response curve is directly proportional to the time delay introduced by
the system; a more sharply inclined curve indicates a longer delay.
As previously implied, a deviation in phase linearity indicates a temporal distortion in the signal or,
more specifically, that the various frequency components of the signal take different amounts of time to
pass through the system.
B.3 Measurement Methods
With the use of a real-time spectrum analyzer and an input signal with known characteristics, such as
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pink noise , and assuming that the signal source and the microphone are linear, we can measure the
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Stressing the system with a known frequency content signal X (f ) and measuring the output signal from system Y (f ), you can
characterize its operating mode, that is its frequency response. Stressing with pink noise and measuring with an octave fraction
     
Figure B.2: Characteristics of the Perfect System
Figure B.3: The Effect of Delay on the Phase Curve
B. Notes on system measurement
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