Walt,
thanks for the reply. I was afraid, that the discussion turned into
a unpleasant emotional debate...
I can not provide the complete derivation of the sound wave theory
here. Read a textbook on technical acoustics. You will find the
rules describing how sound travels in air (and all other stuff
including reflection and so on). I admit, that it is difficult to
understand these effects from viewing at single molecules.
Nevertheless, this acoustic wave theory has proven in practice.
I will do the frequency response measurements in the near future. At
the moment I have no calibrated sound level meter. However, it
should be possible reference all parabola measurements to the bare
MKH 800, which came with a individual frequency response plot. This
would compensate the bad frequency response of the speaker. I will
use a slowly sine sweep signal played back from a laptop PC and I
will record the microphone signal directly into the same computer.
It would then be possible to create a frequency response plot from
these data.
In the mean time you might look at this paper:
Little, R.S. (1964): Acoustic properties of parabolic reflectors.
Bio-Acoust. Bull. 4.
Raimund
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