Vertical Microphone Method
A simple approach to a common problem (aha!)
by Floris van Manen (Klankschap)
"... As we are often recording music that is not truly in stereo, or we are in positions that compromise the stereo image, we must determine how we want to create a feeling of stereo."
There are a few assumptions. The ensemble should play in balance, among themselves and within the
room. If they don't, then it is probably not worthwhile recording at all. Sometimes (most times)
however the ensembles (small or large) are located on stage in a non-stereo alignment. Then you have a
problem, e.g. one doesn't want the percussion of the left and the solo player on the right. We want them all
in the centre, sort of.
The common approach to geographically non-well formed ensembles is to add microphones to the scene and re-arrange the balance through an audio mixer. Yet, the first thing that will disappear from that mixed rendering is the clear room information. Of course one can try to add modern reverb tools, to recreate the acoustics. However the real music in the real room has its benefits too. There is no music without time, there is no time without space...
The world isn't flat
A simple solution in most cases is to take advantage of the fact that we as humans seem to believe that the
world is flat. Instead of recording in the same plane as we listen, we can record in a tilted plane. The
result of rotating the microphones by 90 degrees into the vertical plane is that, in principle, everyone will
be located in the centre of the stereo image. Yet the room information is still available and the music will
sound in situ.
In other words, you make a mono recording within a stereo space.
The best of both worlds...
The picture above shows a real life example. The stage too small forcing the musicians to position them selves in a non-stereo way.
VMM: Vertical Microphone Method (van Manen Method :-)
As you can see the microphone is not left-right but top-down.
The centre plane crosses all musicians.
By tilting the microphones slightly off-axis, one has even control over repositioning the individuals within the stereo image.
In this case two omni directional microphones are used with a small size Jecklin disk between
them. Using the Vertical Microphone Method (VMM) the use of a Jecklin disk is not mandatory (all though
very efficient). One could amongst others also use an ORTF pair instead.
It just comes down to flip the mind and turn the mics into another dimension.
e.g. You turn the orchestra by turning the A-B horizon of the microphone setup sideways (the latter being somewhat simpler to do than the first)
What does this sound like?
What does the Master say?
Jürg Jecklin, the inventor of the Jecklin disk was very pleased with the solution found:
"You are a genius", he said. (and he provided that in written)
Simple, yet effective
I hope this approach can be of any use to some of you.
Questions? Suggestions? Feel free to mail.