Paul, thank you very much for posting this file! Although the book is
long out of print, I think his conclusions are valid and will hold
sway in my choice of microphones for the parabolic I am currently
building. So far, I have purchased a used AT4041 from eBay and this
passage reinforces it's use. Thanks again, and could you scan and
post the rest of this book? :-) Chris
--- In Paul Jacobson <> wrote
>
> I've scanned the relevant 5 pages of the Reflectors chapter from
John
> B. Fishers "Wildlife Sound Recording" and uploaded to the files
area.
> Given the book is long out of print and the extract is small I'm
> assuming it's ok to post this. If not please let me know and I'll
> remove the file.
>
> cheers
> Paul
>
> On 18/07/2007, at 9:36 PM, Paul Jacobson wrote:
>
> > I'm not a dish user so I can't verify the veracity of this in
> > practice, but I was reading John Fisher's "Wildlife Sound
Recording"
> > the other night and came across an interesting tidbit relating to
> > cardioid and omni's in parabolic dishes.
> >
> > In Chapter 5 - Reflectors - Fisher discusses at length tests
carried
> > out by Professor G. N. Patchett of various 24" reflectors which
> > showed a -7dB dip in gain between 600-700Hz. This was attributed
to
> > "... partial cancelation of the reflected wave by the direct sound
> > waves." Several pages later Fisher states "As the cardioid has
very
> > little response from sound waves approaching from the rear, there
is
> > no cancellation of the reflected wave by the direct wave."
> >
> > The graphs accompanying the text show the cardioid+reflector does
not
> > suffer from the dip in gain displayed by the omni+reflector.
> >
> > The text is somewhat dated, but hopeful this information is still
> > relevant.
> >
> > cheers
> > Paul
> >
> >
> > On 18/07/2007, at 7:07 PM, D Secomb wrote:
> >
> >> Hi all
> >> I know this subject as been mentioned recently. It has been
mentioned
> >> that omni are in theory the mic to use in a reflector but several
> >> members state a cardioid is the better type to use. Why?
> >> What is the reason behind the preference? Is it gain, tone
qualities,
> >> low gain of sound outside the focus area or is there something
else?
> >> David
> >
> >
> >
> > "While a picture is worth a thousand words, a
> > sound is worth a thousand pictures." R. Murray Schafer via
Bernie
> > Krause
> >
> > Yahoo! Groups Links
> >
> >
> >
>
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