Marc:
Good idea!
I don't know of any publishes ones.
Rather than white noise, I made a sound file with tones at the same
amplitude and various frequencies, played this back and recorded it with
mic in parabola and similar mic w/o parabola. The difference between
the two I attribute to gain from reflector.
THere's too much background noise in my calibration curve (and I know
nothing about what the speakers are doing) to make me have much
confidence in it. Someone with a controlled setting and good speakers
could do a much better job. If we can get such a curve (clean) it would
provide a basis for renormalizing a parabolic recording.
This is all of great (theoretical) interest to me, and would also have a
value by providing a good starting point for EQing a recording.
On the other hand, and to be practical, I'm happy to go with Jim's and
Klas's comments. They know what they're talking about and what they say
fits in with my limited experience.
In the end, what matters is either what it sounds like or how well it
reflects the real events. Either way, a parabola is essential for most
of what I'm interested in!
Marc Myers wrote:
>
>
> Are there published specs on the attenuation curve by frequency for any
> of the commercially available parabolas? If you are trying to be
> accurate, it seems to me you could record white noise, split out the
> response by frequency and then equalize the inverse.
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