[Elecraft] Why 600Hz?

[Bob Tellefsen]

This is just a recommendation.  The KDSP2 allows you to set any center
frequency that you prefer.

Studies (I have been told) show that it is easier to distinguish two
tones close together if they are both low in pitch.  Say you have 580 Hz
and 600 Hz to separate.  Compare that to perhaps 1000 Hz and 1020 Hz.
The lower pitches are easier to tell apart.

Another factor enters the equation.  As we get older, at least some of
us prefer a lower pitch because it is easier for us to hear.  Seems like
the higher frequencies in hearing are the first to fade.

I have been using 580 Hz, because that's where my acustic filter speaker
resonates.  I'm going to try to retune it to 550 Hz, because the DSP unit
works in 50 Hz steps.

73, Bob N6WG