OPTICOM OPERA Broadcast, User Manual

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C H A P T E R 6 : T E L E P H O N Y B A N D V O I C E Q U A L I T Y
T E S T I N G
129
Figure 6.12:
Result Style Dialog
The resulting diagram is as shown in
Figure 6.13
.
Figure 6.13:
The Spectra diagram
The excitation diagram displays the internal representation (see Section 2.2) of a
signal. The Bark scale is used for the horizontal axis, the vertical axis is scaled in
dB SPL. The curves are shown on a frame by frame basis, without any
averaging.
As shown in
Figure 6.14
, the reference signal excitation, the test signal
excitation and the difference between both excitations can be selected. The
difference is calculated by subtraction in the linear domain, then displayed in
dB SPL.
Excitation