Hi David,
I find the concept of perceived phantom source shift interesting though som=
ewhat confusing. The paper explains "shift" as "the percentage of distance =
from the middle of the image to either of the speakers." The greatest maxim=
um average shift of 104%(shown in Table 2)was found from a Binaural setup, =
and the lowest maximum shift was 81% from a XY setup. Even if they found X=
Y to be most linear, still we are talking of a compression to 50 degrees of=
the original 180 degree horizontal soundstage.
Meanwhile on the nature recording front, soundscape microphone techniques l=
ike Jecklin Dick, SASS, Curt's parallel boundary arrays, and other techniqu=
e can produce much wider spread to significantly outside the speakers, givi=
ng a maximum phantom shift upwards of 200% (or 120 degrees) from a standard=
speaker setup. Some with fairly linear localization also, if that is what =
is important.
John Hartog
oregonsoundscapes.com
--- In wrote:
>
> >> Some years ago there was an AES paper (sorry I can't find it now) on a=
>> shoot-out between a number of popular stereo arrays. ORTF got high mark=
s >> for source positioning accuracy.
>
> Dan,
>
> I have more on another paper below but what I have also found is:
>
> "Choosing and Configuring a Stereo Microphone Technique Based on
> Localisation Curves
>
> Magdalena Plewa1 / Piotr Kleczkowski1"
>
> Link:
> http://www.degruyter.com/view/j/aoa.2011.36.issue-2/v10168-011-0026-8/v10=
168
> -011-0026-8.xml
>
> URL:
> http://www.degruyter.com/dg/viewarticle.fullcontentlink:pdfeventlink/$002=
fj$
> 002faoa.2011.36.issue-2$002fv10168-011-0026-8$002fv10168-011-0026-8.pdf?t=
:ac
> =3Dj$002faoa.2011.36.issue-2$002fv10168-011-0026-8$002fv10168-011-0026-8.=
xml
>
> Spin down past the maths and look at the plots on page 9. These give the=
> object/image localisations for various setups. Figs 6 and 7 compare ORTF=
> with XY at 90 deg.
>
> Back to another email:
>
> > Is it this one
> > http://tinyurl.com/potfwud
>
> John,
>
> I've just waded through this paper and it is assessing distance perceptio=
n
> with different loudspeaker combinations in large auditoriums.
>
> They settled on an ORTF mic setup:
>
> "In a comparison of various stereophonic
> microphone arrays, Hugonnet and Jouhaneau [8] find
> that coincident techniques (such as XY and MS) yield
> the most accurate lateral localization, while closely
> spaced techniques (including O.R.T.F.) yield the finest
> distance discrimination. In another comparison, Ceoen
> [9] found a subjective preference."
>
> The recordings were all done on an ORTF mic rig, after rejecting AB and M=
S
> but "dipole" loudspeakers were included in antiphase. They were only look=
ing
> for distance and special effects, not lateral effects.
>
> However, one reference looks interesting but I haven't located it:
>
> C. Hugonnet and J. Jouhaneau, =E2=80=9CComparative
> spatial transfer function of six different
> stereophonic systems,=E2=80=9D 82nd Audio Eng. Soc.
> Conv., London, Preprint 2465(H-5), 1987.
>
>
> My conclusion for nature recording? Check out your rigs with a shaking
> peanuts test using your ears. :-)
>
> David Brinicombe
>
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