Hello everyone! Since this topic has been very interesting to
me I thought I would come out of lurking mode and attempt to
add something to the discussion.
First a brief intro:
I found this group via a google search. I am a member of the NGSDCS,
"New Guinea Singing Dog Conservation Society". There was a post from
oryoki concerning a field setup we were wanting to put together for
a expedition into the highlands of New Guinea. BTW, that is still
a major goal for the NGSDCS. I don't want to believe they are extinct
in the wild!
My name is Moe Kunkle. While not a nature recordist, I assisted my
sister in the early 1970's with recording eastern Kentucky fiddlers
and ballad singers. Mostly just kept the mic batteries fresh and
r-r tape machine aligned and biased. I went on to become a power line
mechanic with Ky Power before settling in Huntsville Al in 1979.
I went into the pro audio repair and was chief engineer of a am radio
station with a big reputation in the country music industry.
I also worked on retainer, for a local recording studios, keeping their
2 inch Ampex tape machines repaired and aligned in addition to the mixing
consoles and peripherals.
Now to the topic at hand.
I've seen first hand the effects of the e-field present during a thunder
storm.
As the charge builds between clouds or clouds and the earth, I could watch
my
AM antenna detune until the lightning either let go or my VSWR go so off
that
the transmitter would shut down. After the discharge, all would be normal
until
the next charge started to build. This would occur even for storms that wer=
e
miles away.
While working de-energized power lines, it was common for a charge to build
before
a cloud to cloud strike. Again, these storms were many miles away. Cloud to
ground
packed a additional punch if it actually struck the line being worked. Ther=
e
are
many anecdotal stories of cloud to ground lightning traveling miles in the
topmost
parts of the soil. Some taking a detour up one leg, through the body and
down the
other leg of some unlucky soul.
The point is, during the buildup to the strike, the relationship between
electronic
devices and ground (DC as well as AC) is thrown way out of wack. It is a
dynamic event
that gradually detunes the signal to ground relationship within the mic, mi=
c
cable
and the audio path in the recorder, right up to the point of discharge.
Now we have a e-field that is collapsing. This will produce a back EMF fiel=
d
that
also effects the audio path. This back EMF is more transient and quick as
apposed
to the buildup leading up to the discharge.
Throwing in my two cents here, I would consider using the shortest mic cabl=
e
possible.
A low impedance mic is mandatory as well. I would avoid utilizing phantom
power to
the mic. Use a directly installed battery in the mic. If the storm is
displaying
mostly cloud to cloud lightning, keep any cabling perpendicular to the
lightning strike.
The same for cloud to ground.
Anyway, I've enjoyed reading this group. I wish I had a decent setup to
actually record
some soundscapes. I love thunder storms and severe weather events. Firework=
s
displays
are a lot of fun as well. I love the sound of very loud salutes and the
reverberations
off nearby objects. I have a lot of New Guinea Singing Dog sounds, but none
are recorded
with decent equipment. I have two NGSD's that sing daily!
Duty calls,
Feed the dogs, bath the kids........ some of you know the drill:-)
Later,
Moe Kunkle and The AlabamaSingers
-----Original Message-----
From:
Behalf Of Rob Danielson
Sent: Thursday, July 20, 2006 1:03 PM
To:
Subject: Re: [Nature Recordists] More about thunder recordings
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