The Record Producer
Page 72
Chapter 5
The all encompassing reality of wave relationships.
Let us apply this analogy to a studio scenario. Say you are
recording background vocals for a song. You have two female
singers, one panned left and the other panned right. Depending on
the written harmony, this could be a set up for several dbl anomalies.

The windshield wiper analogy illustrates how phasing wave energy
relates to NFR. Frankly, that is all NFR is. ‘Phase’ is a term that only
applies to congruent frequencies, as far as engineering/or any book
on engineering, is concerned. It is important for engineers to view
phase in this way, because it is remedied through time alteration (as
in: when the wave begins). NFR, referring to non-congruent
frequencies, must be applied to Omni-Phase as it is the third
contributing factor in the dbl anomalies that occur at mix position.
More specifically, it contributes to your understanding of everything
that can occur in the environment between the speakers. The
environment we get paid big bucks to influence.

Periodically: one wiper goes up, while the other goes down;
just as one driver will move in, while the other moves out.
Whenever this is happening there is a loss in dbl at mix position.
Whenever the speakers move congruently, there is a gain in dbl. In
the dual vocalist scenario, these gains and losses will be occurring

The varying losses and gains in dbl are the reason certain
harmonies are considered pleasing and others displeasing. So, there
is an equation that creates pleasing harmonies.