Tektronix 070-8811-08 - Manual (Page 42)

Operating Basics
764 Digital Audio Monitor User Manual 27
Figure 21: The 764 phase display
The Lissajous Pattern
The Lissajous portion of the phase display is a plot of one channel
against another on an orthogonal pair of axes. The X–Y orienta-
tion — shown on the right in Figure 21 — plots left channel data along
the vertical axis and right channel data on the horizontal axis,
emulating the conventional X–Y display of an oscilloscope. The
default “Soundstage” orientation , shown on the left in Figure 21 ,
rotates the X–Y pattern 45 degrees counterclockwise so that the
channel data are plotted along diagonal axes, and mono (or in-phase)
audio appears along the vertical (“straight ahead”) axis.
If you are unfamiliar with Lissajous phase patterns and their
interpretation, see Tektronix application note 21W-6244-2, “Stereo
Audio Measurements Using the 760A Audio Monitor.” The concepts
discussed apply to the Lissajous display of the 764 as well.
The Correlation Meter
The Correlation meter, illustrated in Figure 22, displays a true
mathematical phase correlation (mono compatibility) between the
two channels of the phase pair, independent of signal amplitude. You
may find it easier to interpret the correlation meter than the Lissajous
pattern. The position of the diamond-shaped pointer indicates the
correlation between the two selected channels. The meter will read