From: "thorley_tom" <>
> Hi Walter,
>
>
>>>I'm curious about getting surround sound from a single mic? I'm kind of
>
> assuming you are talking some surround sound mic? What mic are we
> talking about?
>
> Soundfield ST250 system http://www.soundfield.com/ comprises microphone=
> and all preamplification etc. the derived signal known as B format can be=
> recorded to 4 tracks and using various Phase techniques extrapolated into=
> 7.1 in post or in the field with a laptop.
I was wondering if you were thinking of that one or some other mic. I'm
familiar with the mic, at least in as far as having downloaded the
owner's manual and so on some time back and studied them, and read
reviews. And had some time to think about it.
>>>And have you tried it in the field? How does it handle humidity?
>
>
> It is designed for the field (indeed you can buy a rycote to fit it) I ha=
ve=3D
> no direct
> personal experience of how it handles humidity but have been told that it=
> does well in humid conditions.
On this, I noted it's got a internal heater to deal with humidity, which
is good, except the heater will not run when it's running on battery
power, only when on AC. That's not going to help for nature recording,
except I guess you could figure out the pins feeding it and rig a power
supply separately (and probably void the warranty).
They go to considerable length to give warnings and methods of dealing
with humidity. The heater and all that kind of makes me think it's
likely to be a problem. They say you should always use AC in humid
situations, and keep the mic running.
In any case, it does mean any reports of how it handled humidity will
have to be investigated for how it was being powered at the time. As
well as how wet or dry the situation was.
While on the subject of power consumption, sort of, note that this
requires 20ma of phantom power. To deliver that much, they suggest that
you will have to modify your phantom power source.
I think it's going to be more like it's a inside mic that can be run off
batteries. Can be used outside under good conditions if done carefully.
This fits with what I noticed years ago about studio recordists. When
they talk about roughing it in the field, they are often talking about
some other building than their studio. This is a little closer to field
equipment, but not a lot, still pretty rooted to the studio. Or at least
the AC line. Need to see a new improved version.
>>>What's it's self noise like, both levels and quality?
>
>
> It's frequency response is ruler flat till16kHz. Self noise is "not as go=
od=3D
> as
> sennheiser or schoeps and comparable with a neuman".
One of the early threads in nature recordists was on what's a acceptable
self noise for nature recording. It eventually settled, more or less on
a figure of 20dBA for a upper limit, and preferably much lower. The info
in the owner's manual says the mic's self noise varies with the pattern
setting. The only pattern that they give a spec is cardioid mid at
17dBA. If one assumes that it does not get worse with other patterns
then it fits under the 20dBA limit. But compare that to my pair of
MKH-80's, which could, either using Bernie's M-S surround approach or
crossed figure 8's give planar surround. They have a self noise of
10dBA. (And can be recorded on two channels) And they sound wonderful!
>>>If it's multiple mics, what mics? What pattern do you use to set them up=
?
>
>
> It is not multiple mics so no setup. It uses 4 capsules. You can decide (=
in=3D
> post
> if you want) whether your mic array is fig.8 / cardiod / hyper-cardiod.
For nature recording it should be noted that the most directional
pattern this mic can imitate is the hyper-cardiod. When I first looked
at this mic I viewed it as a "local" mic. Not something to record
distant subjects or soundfields. I've not changed my opinion. You will
have to be imbedded in what you are recording and it must be relatively
close.
I'm not so sure it's ability to be panned in 3d would give all that true
a picture in the diverse acousitics of the outdoors. I'm pretty sure
that it's accuracy depends on relatively simple acoustic surroundings.
I'd love to play with one and see.
> How the system works is pretty complicated their website explains the the=
or=3D
> y
> very well http://www.soundfield.com/
I had no problem understanding how it works. I'd already waded my way
through M-S and other stuff. This is right down the same line except in
3d. Even with M-S I'm already aware of 3d aspects.
> As a brief aside the HHB portadrive is actually =A36995 ex VAT
Add to that the list price of $5300 for the ST250 and it's getting up
there. Too rich for my pocketbook. Though I have seen a listing for a
ST250 used for $3000. If some fool puts one on Ebay with no reserve and
a very, very low starting price and get's no bids I may just grab it.
Not much chance of that. Even if I had it, I'd be using it as a M-S for
the most part.
For my frog recording I'd want the mic to be surrounded by the subjects
if doing surround. Which means carting it out into the middle of a
wetland/flooded area/swamp, etc. at night. (I wonder how long the cable
between mic and control box can be) Under such conditions my mics often
have dew condense on them, thus the importance of rock solid immunity to
humidity. Of the thousand or so sites I've recorded frogs in Georgia,
probably only a handfull would be suitable. That makes going this route
for me even less attractive. Just changing the conditions to the one
sided recording of stereo opens up a large number of sites that are not
suitable for surround. Like all the sites I describe as recording over
the barbed wire fence with the no tresspassing sign.
I've been getting some feedback from the local users of my frog CD. What
I'm getting there is another reason why I'm not jumping into surround.
Universally, what my local users want to see next is pictures, they are
more than satisfied with stereo sound for listening. And to make a
surround recording attractive that would need to sync to video. Photos
of frogs, once you get past the easy ones, are much tougher than sound
recordings. I don't just record frogs, I photograph them too. I've
thought of doing video with sound, which could be surround sound. Those
of us that worked on the CD have discussed this and looked at possible
options. We are experts at finding and working with frogs, and we have
agreed we probably don't have long enough lifetimes to get all Georgia's
species into suitable video for such a production. So, I'm currently
aimed at some combo of still photos and sound. Which is a less daunting
task than trying to have the video of the frog that's calling on the
soundtrack. (remember, it's recorded in the dark of night)
And if you add the price of HDTV video gear to the price of Surround
sound recording, that's what you are really talking about. I think some
good stuff can be done, but not cheaply, or quickly. Technically, it's
all possible. Practically, much less so. I'm really curious as to the
final product others going into this expect to produce. The gee wiz I
can do surround wears off and you are faced with making something of it
to justify the cost. So, what's the vision of everybody on this? What
final product are you talking about? How will you gather the material?
Walt
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