Hi Greg, Rob, John,
On 04/10/2010, at 9:05 AM, jtudor2005 wrote:
> Do you have some new toys???
Sorry about the previous non-reply. Unfortunately no new toys, just part o=
f the ongoing search for the "perfect" stereo rig for my omni mics.
In this case my interest is in Blumlein Difference Technique (BDT) using ba=
ffled omni's rather than the better know Blumlein pair using crossed figure=
-8 mics. Jecklin apparently developed his disk from the BDT idea.
http://homepage.ntlworld.com/chris.burmajster/Blumlein.htm
The shuffler is used to convert phase difference to amplitude difference be=
low 700hz. My understanding is that the conversion is derived from the phy=
sical spacing of the mic capsules, so it's not 100% clear how to translate =
this into something like Greg's method of shuffling based on mid and side e=
q adjustments. I've replicated Greg's setup in apQualir/apEQ as per Rob's =
suggestion and it looks like this will work pretty well, although I'm fairl=
y certain apQualizr isn't linear phase.
I've also located a great paper on shuffling by Michael Gerzon which has a =
lot of general information on the technique.
http://www.audiosignal.co.uk/Resources/Stereo_shuffling_A4.pdf
There is also a note in the Waves S1 manual regarding use with the SASS and=
other "non-standard" stereo rigs:
"The S1 may not prove very effective on recordings made with a =93binaural=
=94 dummy head, or similar approaches to recording such as the Schoeps =93s=
phere=94 microphone or the Crown SASS system. These systems produce a very =
non-standard kind of stereo, and may not be improved by the S1. These syste=
ms ideally require the use of a different kind of shuffler to that incorpor=
ated into the S1 (further details on this may be found in M.A. Gerzon, =93A=
pplications of Blumlein Shuffling to Stereo Microphone Techniques=94, J. Au=
dio Eng. Soc., vol. 42 no. 6 pp. 435- 453 (June 1994).). Width control may =
not be effective for such stereo microphones. However, although the S1 was =
NOT designed for use with the stereo produced by such microphone, if you li=
ke an effect it produces on them, feel free to use it."
cheers
Paul
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