Scott wrote
> I can't seem to wrap my head around MS and have uncovered a confusing
> issue. I have discovered that after decoding my MS recordings (MDA
> plug-in,Voxengo MSED, or Audition) they are 100% out of phase according
> to Audition's Phase Analyzer. When I invert one channel, they return
> into phase. Where in my chain would I inadvertently be inverting the
> phasing? Or does decoded MS always have an inverted phasing?
Not familiar with Plug-ins you mention. The Audition one is/ can be rather=
confusing & its awful to use IMO. Suggest Kelly industries Stereo Tools,
free & great VST plug.
When you say 100% out of phase this suggests mono to me all stereo has some=
out of phase info.
Q what does it sound like when you sum the L&R out IE mono it?
Q are you using the Phase Analyzer in L/R mode? {not a good idea in MS or
Spin mode}
Q Are you are decoding on the Multitrack page?
If you have a 2 chan file running (IE you haven't converted your file into =
2
mono files) the balance control will need to be centered. Conversely if
using 2 mono files they would need to be panned hard L & R
"Tim Nielsen" Wrote
> It shouldn't be that way. MS 'should' be completely in phase and
> fully mono compatible.
Agree 100%
>
> Are you positive you fed the center mic into the 'left' channel of
> the MS plugin, and the figure-8 to the 'right' side? I'm not sure
> doing it the other way would cause the phase issues you're seeing,
> but they do have to be set correctly.
No, that's not it; Actually it would sound surprisingly similar, there will=
be a problem when (if) you mono'd the output however, you would only hear
the Fig8, IE ambience only.
A proper MS decode will send the M to both L&R [same amount/vol, no messing=
with polarity]
And the S to both too, but with R getting a phase/polarity flipped version=
of S. [again same amount to both L&R chan but this can be the amount you
want to get the stereo width desired ]
The only way to mess up the phase of the decoder output is not follow the
above
So with a proper de-code if you mono the output the S signal cancels ( or
the M if you got your M & S swapped/confused)
The effect of flipping either M or S on the way in would be ONLY to swap th=
e
L R sense. There is an assumption or convention that the S mic should be
mounted with the + phase to the left - if the S mic were mounted the other=
way round all that happens is the stereo field is swapped in a L/R sense.
>
> Are you sure your mic capsules were coincedent? For MS to work
> properly, the capsules need to be aligned in the vertical plane.
>
Reasonable point but it sounds like there's a more drastic prob than a
slight mangling of the HF phase that would cause.
Hope that helps
John Lundsten
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