Metric Halo SpectraFoo - Manual (Page 50)

Instruments
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signals have a correlation of -1, one is the inverse (opposite polarity copy) of the other. When two signals are
unrelated to each other, they have a correlation of 0. Mathematically, the correlation is the average of the
sign (e.g. + or -) of product of the two signals. The SpectraFoo version of the correlation meter has a relatively
fast averaging time to give you a clear picture of the correlation at any given time. To understand how the
correlation is changing over time, you can use the Correlation History meter.
Figure 3.59: Vertical Correlation Meter
Figure 3.60: Horizontal Correlation Meter
As with the Level Meters, the Correlation meter can be put into a vertical or horizontal orientation to meet
your tastes. When the meter is in a vertical configuration it can be docked to the left side of the Correlation
history meter. ( See “Docked Correlation History” )
Correlation History Meter
The Correlation history meter provides you with a time history of the correlation meter. This allows you to see
how the correlation evolves over time and can help you to track down specific phase problems by allowing you
to see “blips” in the phase-correlation at the same time you hear the events that cause the blips. For example,
if the correlation dips every time the snare drum hits, it is very likely that the channels that contain the snare
are causing the problem. Maybe you need to time align the snare mic with the overheads, or maybe that return
on the bussed compressor needs some delay compensation. Other tools in Foo (like the Phase Torch) can help
you track down the solution to the problem. The Correlation Meter and the Correlation History Meter can
help you find the problem.
Figure 3.61: Correlation History
Figure 3.62: Docked Correlation & History