ELUCIDATION OF HOLOGRAPHIC SOUND
This recording-technique is based on physiology and therefore it
is possible to offer very realistic sound wave-fronts
via a normal stereo loudspeaker-equipment.
These modified sound wave-fronts bring the
eardrums of the listener in vibration in practical the same way
as if the same listener is present on the recording-location.
This means also, that the acoustic qualities of the
recording-place are registered, i.e. also three-dimensional
transmitted.
This is an absolute distinct approach, other than normally
executed from a technical point of view.
In the technical way people are thinking from a pure physical
background.
That's why the stereo-recording-technique is restricted to one
co-ordinate, i.e. between left and right.
The whole music is projected on this one co-ordinate and is
offered by two speakers (or headphones) as a pseudo-spatial
sound-image.
Quadrophony was, among others, deduced from this foregoing
concept.
And this last concept is strongly tied to conditions of the
place of the listener and of compatibility.
Of course it is possible to get a reasonable sound with tricks
like phase- and intensity-differences and echo-effects.
What we however are missing are the original physical relations
in an applied physiological approach.
In the holographic sound-technique, the appearing differences in
the sound-frequency-spectrum have consequences for directions
and for the coloring of the recorded sound.
The last is because of the ground- and matching overtones.
Especially excellent musicians are positively impressed with the
present results.
They are surprised by the true position and the true natural
coloring of the sound-images of the instruments and voices in
the holographic registrations.
A distinguishing mark as a piece of evidence for the holographic
sound is the following:
"With the correction of the balance something curious happens.
In the layers of the sound-image an opposite movement takes
place during the correction."(!).
Several questions were brought forward concerning this
system, like:
"Is it possible to
remake an existing repertoire into a holographic one?"
Already recorded repertoire, if recorded on multi-track tapes,
can be realized in a holographic way.
It is possibly to do so, in an electronic process, or via an
amount of monitors, or via a combination of these two.
This electronic process can be found in our technique as
described in the U.S. patent
no 4,393,270. ('controlling perceived sound source
direction')
In this way it is possible to give a musical instrument any
three-dimensional place you like.
You might consider putting a number of monitors in a
concert-hall. Non-manipulated tracks of classical music, can be
reproduced, and via these sound-monitors, then recorded in a
holographic way.
First of all it is necessary to investigate these conditions in
a special studio.
"Is the effect of
holographic sound-image audible in an average room with
average equipment? Or do we need a special room with special
equipment?"
The effect of holographic sound in an average room is of a very
good quality. You can hear the quiet, very wide and deep image,
even outside the room, as very natural and spatial.
During demonstrations in several dwellings, it was clear to the
inmates how very different and how pleasant the music was via
their own equipment.
It wasn't tiring at all, nor forcing and it was very
transparent.
Holographic sound is seen, from the physiological side, so
beautifully balanced, and extremely transparent, that much less
energy is needed.
In this way the listener is not tempted to open up the volume,
in trying to find, what is not there.
"Is the position of
the loudspeakers of any influence at the reproduction of
holographic sound?"
In general, it doesn't matter so much, what the position and the
distance between the two loudspeakers is.
It is possible to put the speakers at some distance, or very
close. Every time it is remarkable, how stable the spatial image
is and how it can be heard everywhere.
Equipment, which physically is neutral in the
listening-room, will reproduce the frequency-spectrum as
balanced as possible.
With such neutral equipment the holographic sound is giving its
special physiological aspects in an almost perfect
way.
"Is it possible to
make improvements in the reproduction-units?"
We might think of an amplification-module, which is adjusting
itself for a neutral reproduction, every time before the sound
is produced.
(This is also appropriate to non-holographic recordings of
course)
This means equipment, having the qualities to adjust itself to a
room with curtains, furniture and carpets and many people, or to
an empty room with its resonance-peaks.
These aberrations can be corrected then automatically with this
module.
For the Hardware this is a very important Unique Selling
Point (USP) (See below)
Too much noise is in fact a very important environment- and
health-aspect.
In our opinion people will cause much less disturbance for their
neighbors, when the reproducing-equipment is getting the above
mentioned qualities.
"Is it possible to use
the holographic sound-technique for pop-music?"
Pop-recordings can be provided with direction-parameters, which
can be used in the 'controlling
perceived sound source direction'-technique, as described
in the US
Patent 4,393,270.
Normally these data are very hard to get (or even impossible),
but with this invention we can.
With the new JOS - Recording System it is now possible to
register these data with an extremely high accuracy and adjust
them.
And we do have now the possibility to use these data in a
computer-simulation-technique, like 'virtual reality'.
"Is it possible
to extend studio-equipment?"
Now it is possible to start with three co-ordinates instead of
one.
The enormous potential of this development in sound-technique
can lead to an extension of the existing studio-equipment.
The 7 USP-s of
Holographic Sound in Soft- and Hardware
From the previous
elucidation 7 important unique selling points are eminent.
- Holographic Sound can be broadcasted and
received via normal equipment.
- Holographic Sound is very compatible, both for
speakers and headphones, in Stereo and Mono
- Existing repertoire can often be made
holographic
- There is a market for the manufacturing of
Automatic Adjusting reproducing-equipment, in order to receive
Holographic Sound(and normal) even better
- There is an option for extension from 1 to 3
co-ordinates for professional studios
- There is a huge market for the 'virtual
reality"
- The possibility to sell holographic
registering equipment for professionals and amateurs
June 1995
J.C.M. van den Berg