Hi Steve,
Yes, sometimes I knock down the higher frequencies which are
disproportionately amplified by the parabola so I can achieve a more
natural sound. Otherwise the recording may sound a bit tinny. The
higher frequencies fade more quickly with distance so keeping the higher
frequencies makes your subject sound closer. This may or may not be an
effect you want. Sometimes the parabola picks up sounds that a person
in the field might not hear and this may give an unnatural feel to the
recording. Remember that all the buzzing bugs and hissy wind are also
abnormally amplified by the dish.
Two other field tricks I've heard Klas mention are to aim the parabola
slightly off axis from the source (bird, ect.) and to mount the mic
slightly deeper in the dish than the area of maximal parabolic
amplification.
For me, the ideal recording would always be to have a MS pair of
Sennheisers right in front of the subject and a long mic cord off to my
recorder. The reality is that my subjects don't often cooperate, so the
parabola gets used. I suppose with enough time and field craft most of
my subjects could eventually be recorded up close with the MS pair. In
the mean time, I love my Telinga Stereo DAT Pro. It's like having a
telephoto lens to use along with the regular lens, both are handy, both
have their advantages and disadvantages.
Kevin J Colver
-----Original Message-----
From:
On Behalf Of Steve Pelikan
Sent: Saturday, June 02, 2007 12:49 PM
To:
Subject: [Nature Recordists] EQ recordings with parabola
Friends:
Sorry for this obviously dumb question, especially from someone who
uses a parabolic reflector quite often but ... I just don't really
know anyone else who does.
Do people generally filter parabolic recordings to "undo" the high
frequency emphasis created by the recorder? I presume that one could
actually calibrate a particular reflector/microphone combination,
determining gain at each frequency and then post-filter a recording
to produce a flatter response?
I've given some thought to actually solving the wave equation
numerically and calculating the gain for a given reflector at
different frequencies. All I've come up with so far is the the gain
vs. frequency curve flattens out faster (meaning at lower frequencies)
in larger reflectors? Does this correspond the the experience of those
who've used several different sizes of reflector?
Thanks for any info...
Steve Pelikan
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