pratap singh wrote:
> Thanks Walter, Rich, Barb Beck and Gernot. My telinga has low and
> high pass and the dish is 22 inch. I have recorded many owls with
> this. Some of the higher frequency recordings are excellent. My
> results for very low frequency are not good. I have not even
> compared performance of telinga with other mikes at low
> frequencies. I had the impression that shotgun mikes can get
> better recordings of very low frequency sounds. I will only be
> interested to buy a shotgun if their is significant improvement in
> the results at the desired frequencies.
At what frequencies do you find the recordings not good? I know the dish
is capable of giving good stuff down the 200Hz or so, the bottom end of
the frogs I record. I know it picks up below that, but for me that even
lower stuff is just interfering sound to what I want, so I don't
critically analyze it. The majority of the time I'm recording with the
low cut in as a result. The keep down some of that sound my mic picks up
because it did not read the theory books.
I don't think it's as much a matter of what's around the mic as how well
it performs as a raw mic at those frequencies. Every mic has a
sensitivity curve in the frequency domain and on top of that may color
different frequencies in different ways. If you are working near the end
of the mics usable range, no reflector or shotgun tube will help it. You
may get poor sound.
I know one mic I'd be pretty certain would handle the low frequencies
well, that's the MKH-110, which was designed to handle frequencies down
to 1Hz, so will be well within it's range with owls. This mic is the one
used in most infrasound recording work. I have no idea if you would like
it's particular sound.
The low end sound I get from mine mounted in a SASS enclosure is much
more precise than even the MKH-20's I also have in another SASS
enclosure. I've not done owls with it, but thunderstorms are even lower
in frequency, going way down into infrasound levels and I have done
those a little. They sound much more like the original with the MKH-110
than the MKH-20.
However, the MKH-110 is a omni, mounted in the SASS enclosure you would
have to think in terms of being very close to record well, it has little
reach, but a very wide sound pickup. It would depend on how loud the owl
was, but would probably limit out at a few hundred feet even with a
pretty loud one, and some of the quiet calls might have to be really
close. This is the same mic that Rich Peet is using in his "football" mic.
The other problem is that the MKH-110 is a long discontinued model,
finding one would be hit or miss.
Beyond that it's hard to judge which mic to use, especially as the
problem is unclear. If at all possible try to borrow the perspective mic
and try it. The raw spec numbers don't really tell you what it will
sound like on the low end. Only listening will tell you how it's
coloring the sound. Being a shotgun mic does not necessarily make it
good. And as noted you don't get much directionality at the low frequencies=
.
Note also you need to be listening with quality headphones, many
headphones don't give good definition at the lower ranges. The same
applies to speakers. I'm one of those folks who thinks the low ranges
should be well defined, which is not a modern trend. It's very neglected.
Unfortunately, the local owls are not calling right now here, or I'd go
out and get a few clips with some of the mics I have to compare. It's
all well and good to haggle over theory, but the real test is to record.
I'll try and keep track and record some when they get going.
Walt
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