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Re: Microphone (stereo) test, what do you think?

Subject: Re: Microphone (stereo) test, what do you think?
From: "John Lundsten" lundsten_john
Date: Mon Jun 6, 2011 7:11 pm ((PDT))
Avocet ans re H=E5kan, post
> I want to (learn to) handhold it because sometimes I want to follow
> for example a Woodcock flying.

I used to teach trainee boomswinigers the "slack arm" method. You
don't grip the boom or mic firmly but with a limp wrist (don't worry -
nobody will notice.:-) ) Similarly, your arm muscles should not be
taut and should retain some "give" compatible with holding the mic in
place.

Agreed, but panning with "a Woodcock flying" as against keeping tolerably
on-axis to an actor who is walking & turning & the mic is less than 1 meter=

away from the mouth has very different requirements.

Some aspects & differences
Nature recording;
you may want to have Much lower frequencies clean & usable and record much=

quieter sound sources as compared to good dialogue recording, where even
with deep voiced Male actors one can savagly cut everything below 80Hz & th=
e
result still sound very fine.

Most, mic suspensions are pretty rubbish (when either violent movement as
may be needed for Film/TV  dialogue recording, or when trying to record
really quiet sound.)

It is quite possible to make good music recordings with no mic suspension o=
r
isolation at all, the level of the wanted sound is massive compared to
vibrations transmitted through the mic stand.

Some/many suspensions just reduce mic stand vibration enough to be of use
for somewhat quieter music sources such as string quartets.

There are some great new suspension designs such as the Rycote Lyres, that=

are "magic" for Film/TV use.

Ok they are not really magic, they do for sure obey the laws of physics, bu=
t
work way better than most previous designs. But good as they are, do bear i=
n
mind at Hz below what is required for good dialogue recording they are not=

at all good, this is not a fault, just a sensible design decision.

Some basic physics.
1) the bigger an object, the lower will be the fundamental frequency at
which it will vibrate the most (the resonant frequency)
2)  so for a low mass object you can isolate it from external vibration by=

having a Very soft, very "bouncy" suspension made typicaly of rubber or
springs. A practical problem for say small mics is that to get good
isolation they will not be able to be "pointed" in a particular direction,=

because they will be wobbling about too much.
3) as the mass gets larger, the stiffer the suspension can be, the "Lyre"
mounts are quite clever in that the required "stiffness" can be different
for each axis..

So, that being the  physics.
For nature recording;  A stand/tripod makes a lot of sense.

But if you need to move the mic during a recording: I reckon if "outside"
you will need a "blimp" or windshield - this will add to the mic weight so=

increase the total mass (+ point).
a) A big minus point is that any LF vibrations, like you holding the hand
grip will almost certainly be of sufficiently low frequency to bypass most=

suspensions.
b) So the looser, or  most "limp wristed"  way you can hold the mic the
better.
b1) holding the mic +windgag handle by your thumb & forefinger is good. But=

not so good for accurate "aiming".
b2) dangling the mic assembly, via an elastic band (or 2-3-4) is better.

John L







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