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Re: MS stereo imaging problems with MKH30/50 combo - Sounds are swap

Subject: Re: MS stereo imaging problems with MKH30/50 combo - Sounds are swap
From: "ajustend" ajustend
Date: Mon Oct 15, 2012 4:58 pm ((PDT))
That definitely makes sense, especially when I picture the equivalent coinc=
ident pair of super-cardioid mics (in this case a set of MKH50's in an XY s=
etup) and the resulting orientation of their rear lobe, which would be poin=
ting directly at the 4-5 o'clock & 7-8 o'clock positions.

Thanks!

--- In  Michael Raphael <> wro=
te:
>
> The mkh 50 is a HyperCard so it has a rear lobe. That is what is causing =
the swapping when you decode.
>
> On Oct 15, 2012, at 5:00 PM, Martyn Stewart <> wrote:
>
> > Is there a chance you could post an example, Justin? I would like to ta=
ke a listen to your ordeal...
> >
> > Martyn......
> >
> >
> > On Oct 15, 2012, at 10:59 AM, "J. Mullens" <> wrote:
> >
> >> Hi, this is my first post to Nature Recordists.
> >>
> >> I have just added an MKH 30 to my collection in order to expand into M=
S
> >> recording and am experiencing very bad imaging (side swapping) with th=
e
> >> setup when the sound source is located in certain places behind the
> >> microphone.
> >>
> >> To clarify, I am *not *trying to record a surround signal using a ster=
eo
> >> mic setup, but I *am *interested in maintaining a correct left-right s=
tereo
> >> image. When I use an XY setup, or an XY mic like a BP4025, anything on=
 the
> >> left side of the mic (in front of it or behind) will playback out of t=
he
> >> left speaker. Using the MKH30/50 combo this is not the case.
> >>
> >> Here is the test I conducted: Set the microphones up in the middle of =
an
> >> open field so that I can walk in a full circle around it. I start dire=
ctly
> >> in front of the M/S setup, about 15-20 feet away, and walk in a clockw=
ise
> >> direction around mic calling out each position on the clock face. 12 i=
s
> >> directly in front, 1, is to the right of that, 3 is directly to the ri=
ght,
> >> 6 is directly behind, 9 is directly to the left side, etc.
> >>
> >> Here's the problem, when I get to the 4 & 5 o'clock postions (rear rig=
ht
> >> side) the sound source swap sides and sounds like it is coming from fr=
ont
> >> left. And the exact opposite happens to the 7 & 8 o'clock positions
> >> sounding like they are coming from the front right.
> >>
> >> Again, any source originating in the 180 degree arc in front of the se=
tup
> >> performs beautifully and the stereo image is perfect. It only happens =
to
> >> sounds coming from behind the mics, and if a sound source is making a
> >> constant tone you can actually hear it jump diagonally across from one=
 side
> >> of the stereo field to the other as it enters these rear right & left =
areas.
> >>
> >> After asking around it has come to my attention that the closer your M=
id
> >> mic is to a pressure-gradient mic (figure 8 polar pattern), the more o=
f a
> >> rear lobe you have, and thus the more chance you have of that rear lob=
e
> >> picking up sound in the opposite channel. This definitely explains how=
, and
> >> why, I could be experiencing side swapping.
> >>
> >> Since I've never used an MS setup with a pure cardioid mic I am wonder=
ing
> >> if the same thing happens... For those using a Sennheiser 30/40 MS set=
up:
> >> does this happen? Do you have side swapping in the 4-5 o'clock and 7-8
> >> o'clock positions?
> >>
> >> Nature recording is, for me, one of the areas where a really accurate
> >> stereo image in a 360 degree circle around my recording location is
> >> critical. I am always pointing my mics at the source I am recording, b=
ut
> >> having sounds behind the mic appearing in opposite channel is just wei=
rd.
> >> How do the MS recordists on this forum deal with this?
> >>
> >> Thanks!
> >>
> >> -Justin
> >>
> >
> >
> >
> >
> >
> >
> > ------------------------------------
> >
> > "While a picture is worth a thousand words, a
> > sound is worth a thousand pictures." R. Murray Schafer via Bernie Kraus=
e.
> >
> > Yahoo! Groups Links
> >
> >
> >
>








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