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Re: Am I looking for omnidirectional or not?

Subject: Re: Am I looking for omnidirectional or not?
From: "Walter Knapp" waltknapp
Date: Sat Sep 1, 2007 10:37 am ((PDT))
Posted by: "paulmcnelis"

> As I continue to do my homework, I am finding out that the WL183's are
> omnidirectional.  And omnidirectional is great for true stereo imaging
> in 360. Sounds great. But is this good for ALL nature sounds - from
> forest ambience to babbling brooks to bird calls to buzzing bees?

No, no mic is good for everything.

Omnis only give you stereo if you separate them by a ways or use some
sort of barrier to modify their all around field to be directional. Two
omnis close together with no barrier will just give you two channels of
near identical mono. Having two mics widely separated out doing nature
recording is very limiting, you won't have the mobility of handheld setups.

The thing about good stereo is that it accurately reproduces the space
recorded, everything can be located by the listener in the same
relationship it was in the original. Stereo like this is not 360
degrees, it's mostly just the field out in front of you at best. You can
get into surround recording to go 360, but that's more recorder
channels, more mics, and much more complex to setup. We really don't
hear in surround, but in stereo. You should fully understand recording
stereo before getting into surround.

Forest ambiance particularly if it's quiet will need a quality wide
pickup stereo mic setup for the best recordings.

Babbling brooks may need the same setup as the forest ambiance. Or they
may need a narrower pickup stereo. It may even be best to record a
stereo of the brook and then mix in some carefully positioned mono mics
to get what you want. A really good recording of a babbling brook is
tougher than it might seem. Same with things like surf.

Bird calls, by themselves, a narrow field mic that can pick up at a
distance is generally best. You can use fieldcraft to get mics close if
the bird has a standard calling location. If you can't get quite as
close or the bird is moving around a shotgun may do. But the king of
picking out a individual caller is the parabolic mic, and the ideal in
this area generally comes down to one mic, the Telinga. If you wish bird
calls with their natural surrounding ambiance then modifications of the
ambiance recording techniques are the route to go.

Buzzing bees:  Well, a single bee will be like the bird recording. A
group of bees will be a wider field, maybe similar to the babbling brook
to record. Probably essential regardless to record in stereo.

I primarily record frogs. Unlike birds frogs mostly call in groups,
called choruses. And it can be multiple species scattered all over the
wetland in subgroups. I use the full range of my mics for these
depending on circumstances. And stereo really is important to pick out
the subgroups.

One of the things you will discover first is just how much unwanted
noise you are going to pick up. Omni's strength of picking up from every
direction is also it's weakness in this regard. You can minimize noise
from a direction different from your subject by using a directional mic.
Nothing will escape the sound of a airplane anywhere in the sky, however.

> Or in order to capture all of these sounds, will a shotgun mic like the
> ME66 serve my purpose?

A shotgun mic gives you a somewhat narrow pickup, cutting out a lot of
the sound from the side. It gives you no extra gain relative to it's
self noise for picking up distant sounds. For extra gain for distant
sounds a parabolic mic is the thing to go with.

While it may seem to you that you have a single purpose, in terms of
technique and mics needed you have described a wide range of different
purposes.

> Or can the NT4 suffice as well?

For some uses where your subjects are not too far away. Also if your
ambiance you want to record is fairly quiet the NT4's self noise will
interfere. For recording individual calling birds it's probably not the
way to go.

Ambiance is where you will get into needing very high quality mics, more
than any other aspect of nature recording. Low mic self noise is
essential in this area.

> In order to pinpoint the type of microphone I need, I need to figure
> out what omnidirectional is better for and what shotgun is better for.

Omni's pick up sound from all directions, more or less evenly. Shotguns
use a interference tube to pick up from a moderately narrow direction.
Shotguns do not provide extra gain, though some are more sensitive than
omni's or cardioids.

Omni's are also slightly more resistant to wind noise. The difference is
minimal, and you will have to wind protect whatever you use.

> Whichever type is better for ALL sounds, I would appreciate your advice!

There is no such microphone. For the wide range of sounds you are
talking about you will, in the end, need several different mics.

I use a set of mics that are above your price range, but here's the main
mics I carry:

Modified SASS/MKH-20 This is my close in widefield stereo mic, also my
primary ambiance mic. Can be used at a fair distance with amplification
under certain conditions. This is omni mics used with a boundary.

M/S MKH-30/40  A slightly narrower field than the SASS, also for close
in. The MKH-30 is a figure 8 mic and picks up the difference between the
two sides of the stereo field. The MKH-40 is a cardioid mic, polar
pattern less than half a circle and picks up the sound coming from the
front.

M/S MKH-30/60 The MKH-60 is a short shotgun mic, so this I use for a
narrower stereo field. Again, with amplification this can be used at
moderate distances.

M/S (and coincident stereo) pair of MKH-80's  The MKH-80 is a multiple
pattern mic of very high sensitivity and very low self noise. You have
in one mic omni, wide cardioid, cardioid, supercardioid and figure-8. So
this setup can record from a variety of stereo field shapes. I'm still
exploring all the uses for this setup.

Telinga Parabolic with Telinga Stereo mic  If it's a distant caller,
this is the mic, especially if you need to reject sounds off axis. Also
if you need maximal side rejection for a closer caller. It has a narrow
distant pickup with lots of gain plus the more local wider stereo field.

All that set is stereo, and every mic except the Telinga came from ebay
at a huge savings over new. It took years to accumulate to replace
earlier less expensive mics. Note how the set is a series of varying
shapes and sizes of pickup field. Here's a couple pages that show most
of it:
http://frogrecordist.home.mindspring.com/docs/mod_sass.html
http://frogrecordist.home.mindspring.com/docs/ms_setups.html
Telinga's website:  http://www.telinga.com/

Here's a page for a concept for building a mono parabolic fairly cheaply:
http://frogrecordist.home.mindspring.com/docs/quickparabolic.html
Mono parabolics are easy to make, stereo ones a bit more tricky.

A pair of AT3032's will work to make a fairly decent modified SASS
that's a lot less expensive than the MKH-20 version.

As others have pointed out you are asking about a wide range of
recording techniques in nature recording. Thus a wide range of mics.
Your budget is such you will probably find the mics you buy you will
later replace with better mics as you progress. You will find out the
most about what mics you need by getting out there and doing. Mics are
the key to good recording, you should go for the best you can afford,
choose with care.

Also technique and experience are very important. You cannot expect to
buy even the best equipment and then it will make the best recordings
automatically. In the end you make the recordings.

Walt




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