THE ART OF SOUND - THE PLEASURE OF MUSIC
'' Human beings do not live in the objective world alone, nor
alone in the world of social activity as ordinarily understood,
but are very much at the mercy of the particular language which
has become the medium of expression for their society. It is
quite an illusion to imagine that one adjusts to reality
essentially without the use of language and that language is
merely an incidental means of solving specific problems of
communication or reflection. The fact of the matter is that the
'real world' is to a large extent unconsciously built upon the
language habits of the group.
No two languages are ever
sufficiently similar to be considered as representing the same
social reality. The worlds
in which different societies live are distinct worlds, not
merely the same world with different labels attached... We see
and hear and otherwise experience very largely as we do because
the language habits of our community predispose certain choices
of interpretation. We dissect nature along lines laid down by
our native languages.
and types that we isolate from the world of phenomena we do not
find there because they stare every observer in the face; on the
contrary, the world is presented in a kaleidoscopic flux of
impressions which has to be organized by our minds - and this
means largely by the linguistic systems in our minds. We cut
nature up, organize it into concepts, and ascribe significances
as we do, largely because we are parties to an agreement to
organize it in this way - an agreement that holds throughout our
speech community and is codified in the patterns of our
The agreement is, of course, an implicit and unstated
one, but its terms are absolutely obligatory; we cannot talk at
all except by subscribing to the organization and classification
of data which the agreement decrees. Individuals who regard
writing as fundamental to their sense of personal and
professional identity may experience their written style as
inseparable from this identity, and insofar as writers are
'attached to their words', they may favor a Whorfian
And it would be hardly surprising if individual
stances towards Whorfianism were not influenced by allegiances
to Romanticism or Classicism, or towards either the arts or the
sciences. As I have pointed out, in the context of the written
word, the 'untranslatability' claim is generally regarded as
strongest in the arts and weakest in the case of formal
scientific papers (although rhetorical studies have
increasingly blurred any clear distinctions). And within the
literary domain, 'untranslatability' was favored by Romantic
literary theorists, for whom the connotative, emotional or
personal meanings of words were crucial''. [from :
The Sapir-Whorf Hypothesis - Daniel
Our bigger projects: the road from important works to the
Some of our
activities : Room
acoustics improvement or new constructions for sound recording
facilities: Studios, TV, amphitheatres, music halls or dedicated rooms
for listening music. One project was Thanos Mikroutsiko's recording
studio where he already finished enough professional recordings.
GIALINO MOUSIKO THEATRO
in Athens (the
Gialino Teatro's site is here),
our most complex project, maybe, is the best music hall in Greece, built
with the previous acoustical materials technology and very expensive.
We design and supervise special sound insulation constructions for any
industrial or naval situation.
Our bigger industrial project
was a successful prototype sound insulation of machinery engine room to
a 110 meters cruise ship ''Princess Danae'' and a much bigger one, a
Greek military complex of 16 tank motors testing chambers. It is
finished a full project heavy sound insulation, interior acoustical
design and 12 KW audio array-a multipurpose hall in Sparta.
We were invited paper at the
Acoustical Society of America's Pittsburgh 2002 Poster Session: Halls
for Music Performance: Another Two Decades of Experience 1982-2002. We
presented ''THE GIALINO MOUSIKO THEATRO''.
In Greece, a paper about the
ROUNDFFUSOR1, was presented at the first Congress of the Hellenic
Institute of Acoustics (HELINA) University of Patras, September 30,
2002. HELINA is a member of EUROPEAN ACOUSTICS ASSOCIATION (E.A.A.).
In Romania, a work about the
corrected studios of the State Romanian Broadcasting Co. was presented
at the Second International Conference of Romanian Society of Acoustics
on Sound and Vibration (is a member of EUROPEAN ACOUSTICS ASSOCIATION (E.A.A.),14
– 17 October 2004, Bucharest.
In Romania again, a work about the Resita's renewed and acoustically corrected
City Hall was presented at the International Conference of Romanian Society of
Acoustics on Sound and Vibration (is a member of EUROPEAN ACOUSTICS ASSOCIATION
(E.A.A.), 21- 24 October 2009, Resita .
In the last months, 15 new
recording studios were built or acoustically corrected in Athens, 2 more
in Thessalonica and 6 new studios abroad [ 4 in Romania and 2 in Holland
], all using our Roundffusor1. Twelve of them are built using ONLY the
Roundfusor1 with or without small carpets on the floor, the same for
control room and all recording rooms. In Athens, the new Eurosound's
demo room, it was built only with R1 on the ceiling.
He who rejects
change is the architect of decay. (Harold Wilson)
Make everything as simple as possible, but not simpler. (Albert
man who cannot occasionally imagine events and conditions of existence
that are contrary to the causal principle as he knows it will never
enrich his science by the addition of a new idea. (Max Planck)
We excuse that
we don't have too many representatives around the world (we work hard on
this). Until you will have a representative near to your place, in order
to hear and believe that our R1 is indeed so good, please note that
there will be always experts to say Forget it: such things are
study based on 1950's work by a psychologist we have some unexpected
The unpleasantness of standing alone can make a majority
opinion seem more appealing than sticking to one's own beliefs. If other
people's views can actually affect how someone perceives the external
world, then truth itself is called into question. See more
we try to improve the World's architectural acoustics data and attitude
The Roundffusor1 is in a totally new category, a giant step in the art
of acoustical materials !
description of our invention
ideal [overall] predicted sound diffuser polar plots, something thought
and desired, but difficult to believe as being ever practically
UNTIL NOW !
Above, a more specific prediction [using Matlab] for scattering from
hemispheres and hemi cylinders, variation with distance.
Regarding the Roundffusor1 which is built from a complex combination of
hemispheres and hemi cylinders , please note that our device when
grouped mounted, is simultaneously a very active diffuser and much more
complex Helmholtz resonator and, the combination of two is almost
impossible to be emulated into an equation. We may say that the
superposition principle is somehow the explanation phenomenon, but not
This two examples are the ''ideal'' or best predicted polar diagrams
( from bibliography ) for situations similar with the Roundffusor's
measurement setup. The heavy lines (hemicycles) represents 99%
diffusion factor, and the incidence angles are : a) 0, b) 30 and c) 60°.
The Roundffusor1's measurement were made at 45° and the above Matlab
calculations are also made for 45°. Please note that the Roundffusor1
was measured with a TEF20, in a range from
Generally, please note that almost all predicted plots found in the
bibliography or other acoustical materials characteristics are results
from programs working down to 125 Hz only. As you know [ and the
High-End users knows better than all because they are paying hard for
this] the bass contents determine the so named ''body'' of music, his
bass contour containing a plethora of musical information which
transmits to our ears the intimate feeling of each source we are
approaching by. So from most PC's predictions, the ''abyss'' bellow 125
Hz is unknown or not included.
off axis polar plots '' from another company '' (as far as we know that
their provenience is reliable), are chosen from the best of their
diffusers, also at 45° and similar measurements setup.
''forced'' to say , that the Roundffusor1 polar plots , are similar in
many ways with the ''ideal'' ones. Hopefully for us, the listening tests
out-performed and anticipated the excellent TEF20 measurements.
present the following polar plots diagrams from diffusers applications :
a) a case study were the R1 was used as room treatment, b)- a QRD
diffuser type from an US company and, c) - a gypsum pyramid diffuser
from a US Co. You may compare them with the '' ideal ones'' diagrams
and have your own opinions.
Few detailed R1's
measurements are here
Cluj - Napoca - Romania. State Radio station
control room. All polar plots were obtained from a 45 deg.
case study - Comments:
1. The R1's
correction factor it was limited only by the loudspeaker's
low frequency capability installed there.
2. The measurements
were made into the control room shown below
3. The Roundffusor1
were mounted directly upon the absorption material found there. After
the R1's treatment, the rest of the studios surfaces, except R1's
covered ones, remained with the absorption materials as built before.
4. Please note, that
R1 was effective even mounted upon and between absorptive materials. The
tiles in the ''after'' correction, tends slightly to left indicating
that the existing absorptive materials, quantitatively, covered a much
more surface on the left surface of the studio as we look at the
It was demonstrated elsewhere that when relatively bigger absorptive
material are used in a room, this surface tends to emulate an air
duct's flow directivity meaning that the sound as perception is
oriented there like a monaural phenomenon. Needless to say , this
will reduce the stereo image...the stereo image will bend towards
the bigger absorption surface, like a directed jet fluid.
It is an
evidence that using the Roundffusor1 the acoustic field is ''forced'' to symmetry,
or ...the wrong stereo image becomes a wide natural well defined stereo
Measurements made before
the acoustical treatment with R1
treatment with R1
critical Roundffusor 1's measurements
Here are the
critical Roundffusor1's measurements (which at a later stage
will be provided by the various independent laboratories in order to
confirm our measurements and for which I
will not pay, because you never
have to pay for the near perfection situations) showing
that the R1's plastic body doesn't vibrate - so doesn't produce
sensible second generation sound/harmonics, and , that the air from
the R1's back Helmholtz resonator function is having a double role -
first an adaptable damping for low and very low frequencies up to
181 Hz and beyond this and second, that the mid and high frequencies
levels are drastically reduced (only from the space of the grouped
mounted R1's back cavity) with about 10 to 25 dB , this explaining
the dramatically perceived and measurable RT60'S reduction in empty
rooms containing only the R1. The front R1's surface, don't forget ,
is producing the clean diffused field, enhancing the room's loudness
field by a factor of 1,5 -2. This is a paradox, and the
superposition principle is called to solve it.
that in this life and universe, the good luck and intuition or
randomness plays a constructive role, name it evolution, or Ancients
unveiled dormant memory, sometimes, as in the Roundffusor1's case
were a design progression of interrelated phenomena evolved in this
patent. To ''switch'' from dormant memory ''data base'' to a higher
cognitive development is possible, although by no means easy. So,
read otherwise...R1 was designed by mind.
Here a relevant text (Chomsky and the Universal Grammar) .
Reading from Carl Jung's philosophy of memory , the ''FIFTH LEVEL:
INTUITION ~ This is the ultimate level, where learning becomes
connected to your experience. This is the stage where you begin to
make connections between things you learn in one class, and things
you learn in another. You begin to see that everything connects, in
some way. You begin to see the way “the big picture” looks! You have
to work toward this level, but the reward is a lifelong appreciation
of the very process of seeking knowledge''. And everything is
connected to a society - here a new
Don Cruse -
The Embattled Ideal of an Open Society.
ideas : Concerning Science, Religion, Logic, and the Evolution of
Human Consciousness, relevant texts
over matter or... ''intuition is to thinking what observation is to
Or, if you prefer, stay put in the
for acoustical materials (diffusers) from another companies
b) Here are the polar
plots of a diffuser (QRD Type) from an US company
are the polar plots from the same US's Co. - a gypsum
>>> Regarding the somehow not symmetrical diagrams above (a&b) ,
it was demonstrated elsewhere that when relatively bigger absorptive
material surface is used in a room, this surface tends to emulate an air
duct's flow directivity meaning that the sound as perception is oriented
there like a monaural phenomenon. Needless to say the stereo image it
will be blurred and
stereo image will bend towards the bigger absorption surface, like a
directed jet fluid. If the absorption surfaces are symmetrically mounted
upon the lateral walls, then the predominant channel will split in two,
like monaural signals.
Diffusion or absorption ?
than 70 years ago, prestigious scientists remarked and proposed the use
of diffusion instead of absorption in all qualitative acoustical
situations. Interfering reflections can be controlled by absorption or
small and medium sized rooms, it is often desirable to control
interfering reflections, from the rear wall, using diffusion instead of
absorption. In this way you can provide a diffuse ambient sound field,
while controlling interfering reflections.
When the room's surfaces are relative close to the listener, a very
efficient diffusing surface is needed, this because as known, the
smaller the room the most difficult to smooth the many resonance modes.
To solve this problem, ONCE AND FOR ALL, ESR by its owner and
acoustical consultant Zainea Liviu, designed, patented and then produced
When the shape / geometry determines the function, in
the design effort, subconsciously, it may reach the Mandalas sacred
symmetry or the Chladny evident also symmetrical situations. More,
perhaps I was influenced in its design by the purity and simplicity of ancient
Greek art. As much as archeology unveiled the past, the ancient Greeks used no
absorptive materials in their theatres, just hard materials and ingenuity...The
subjective geometry / aesthetics perception should be subordinate by the very
performance, an unique situation in the architectural acoustical field.
Now, the Roundffusor1 it is the industry first,
and from far away, the most efficient sound diffuser.<< I
agree that all this statements are at the edge between
arrogance, but please,
take all this as self-confidence or deep joy resulted from the
outstanding invention's performances. And deep joy from musicians using
the R1, is much more satisfactory and comes to me all the time.
I am indebted to the earlier work done by Peter D'Antonio, PhD & CEO
and his collaborators at the RPG Diffuser Systems. Without their
previous efforts, my invention couldn't be so quickly possible.<<
R. Schroeder, around 1975)
About real technological progress you
may read ''
'' The perfectly * diffuse sound field ''
though unattainable ( they said ) , it is
instructive to consider the characteristics of a diffuse sound field.
Randall and Ward’ have given us a list of these:
frequency and spatial irregularities obtained from steady-state
measurements must be negligible.
• Beats in the decay characteristic must be negligible.
• Decays must be perfectly exponential, i.e., they must be straight
lines on a logarithmic scale.
• Reverberation time will be the same at all positions in the room.
• The character of the decay will be essentially the same for different
• The character of the decay will be independent of the directional
characteristics of the measuring microphone.
These six factors are
observation oriented. A professional physicist specializing in acoustics
might stress fundamental and basic factors in his definition of a
diffuse sound field such as energy density, energy flow, superposition
of an infinite number of plane progressive waves, and so on. The six
characteristics suggested by Randall and Ward point us to practical ways
of obtaining solid evidence for judging the diffuseness of the sound
field of a given room. From :The Handbook of Acoustics-3rd Editions- F.
Alton Everest, TAB Books, page 223. (*
Personally I don't agree with the term '' perfect ''. For this reason I
use ''near perfect'',
even if the Roundffusor1 is making beautiful and ''perfect'' the sound
ROUNDFFUSOR1 FULFILLS ALL THE ABOVE CONDITIONS!
PHILOSOPHY & HISTORY AROUND ACOUSTICAL MATERIALS ARE IRREVOCABLY
What is the Roundffusor1 and how it works
present here a new kind of a sound diffuser, enough simple in his
construction but very active in doing his job. It is composed from a
main body and two lateral drivers. This two drivers serves to sustain
very steady the diffuser upon the surface to be mounted: walls or
ceiling. This diffuser may be used in any kind of room where the
critical listening is needed. His main advantage is that it is working
simultaneously in two ways: as a clean diffuser for mid and high
frequencies and as a self controlled absorber, below 250 Hz, for low and
very low frequencies. This is possible, because being mounted in a new
way, works like a complex Helmholtz resonator.
real time, there is a kind of reconstruction of all music
characteristics – parts diffused or absorbed or both. Even for the
trained ears, there is no time to percept when and how the music is
processed and the listener is just immersed in the sound without any
trace of coloration. The ‘’ historical’’ focus place of listening,
invention is relative simple as an object but being very easy to be
installed by anybody with simple tools and being also very cheap ,
will let the people to buy their beloved stereo equipment or
professional electronics and put them in a room where the acoustical
environment will become also... a ''professional tool''.
Believe it or not, this ''tool'' exists - there is no other like this
and in the rooms treated with our Roundffusor1 there is no place and no
need for any other acoustical material. The reason is simple: the
Roundffusor1 is doing all that is necessary on a minimal surface.
It's the useful change and I'll not exaggerate at all that, regarding
the audio field, after the phonograph, transistor & valve and the audio
CD, the Roundffusor1 is the most mass orientated product on the market.
fully responsible saying that all other acoustical materials besides
their more or less announced and true diffusing function, are
''performing'' a so much damage on mid and high frequencies - there when
the music plays, so much that the absorption ''induced'' is actually
removing the essential from music.
In fact, the
inertial ''traditional'' absorption removes
the natural feeling of a real human musical performance !
the precedence effect, it is also soften. Axial or left / right head
movements don’t arrives to dramatically induced changes. There is an
incredible stability of sound image. At the first sound heard from the
loudspeakers, the listener, instinctively [meaning very quickly,
something between 0.1 to 1 second] focus the ears/ eyes on the location
of each musician. During the music, all those spatial references, are
easily memorized / visualized by the listener. More, if the musicians
changes their places, or are moving here and there, their movements are
easily sensed. In a way, you may VOTE
to see what kind of ''room decoration''
is your preferred one.
Roundffusor1 have NOTHING in common with the ''QRD - Diffractal / RPG''
type diffuser, or with any of their products, just being much better
overall and of course substantially less expensive.
One of the
things that might be a key ingredient in the design of R1, is that
scattering from spheres / hemi spheres produces focusing on a line
behind the sphere. This line lies inside the wall , considering the
original source, but the scattering from the virtual image source will
focus sound into the room. Thereby the scattered sound may be heard at
long distances from the R1. The same might happen with the cylindrical
parts of the R1, but to a lesser degree. In this way the scattered sound
may perhaps be audible at longer distances from the R1 than from other
diffusors. Because real sound sources aren't point-like, and since the
hemispheres on an R1 wall are close to other scattering objects, the
focusing will be somewhat smeared, which in turn might reduce any
negative effects of focusing.
Roundffusor's subjective phase perception ( and easily measured ) is
near zero phase or, more correct - no irregular phase curves, regardless
the center frequencies or music bandwidth. All this phenomena are valid
and perceived at more than 6-7 meters - for average audio cultivated
people and even to 12-14 meters for very trained ones- from the music
source and the '' critical focused point of listening '' or '' sweet
<stereo> spot '' is obsolete.
discussions are easy in the rooms fitted with Roundffusor1 - the voices
are clear and not influenced / disturbed by the acoustical field.
Speaking, you understand that the room is almost empty from '' strange
materials'' , but any kind of echoes or anything which may interfere and
disturb the intelligibility are simply NOT THERE.
a kind of ''aura'' envelope reconstruction from the initial room's
recording session is obtained. The clean perception for speech or music
arrives at all levels- from about 50 dB SPL to the personal pain limits.
Think that all this arrives from a very hard plastic area-of at least 9
Roundffusors1, mounted on the back wall or ceiling and, ... there is
nothing to be changed on your electronics.
OF MID AND HIGH FREQUENCIES
REMOVES THE PLEASURE FROM THE MUSIC
Here is an interpretation about the damages ''obtained'' when using
absorption in a room dedicated to music: '' As
a result, the "naturalness" of recorded is destroyed, and its
ideological effect severely curtailed, if not totally obliterated. The
result is double-alienation, both material and formal there is an
emphasis of distance-the distance between the musician and the listener,
the distance created by the mediation of recording and playback
technology. Unlike with less self-critical rock, there is no "insistence
that nothing a man comes in touch with may be better, or may be regarded
as better, than he himself is or thinks he is" (28). The lo-fi listener
encounters a form, as a form-and not any transparent font of "emotion,"
etc. The music may still be pleasurable, but it is pleasure in a
cultural product which refuses to be merely what it appears to be, which
constantly puts its very ontological status into question. In a world
dominated by the cultural industry and its products, such pleasure seems
to be, in a way, progressive-even if not in the sense that Adorno would
favor. [Play "It's Only Lena."]''.
The live or recorded music will sounds
beautifully similar from room to room
THE SO CALLED INTERCHANGEABILITY OR
REPEATABILITY BETWEEN VARIOUS ENVIRONMENTS IS ACQUIRED
The inventor - Zainea Liviu Nikolae
What matters ? The
of the Invention or the tenacity
of the Inventor ?
The people perceive
only the quality of the Invention
The Roundffusor1 was invented
by Mr. Zainea Liviu Nicolae who studied mechanical engineering at the
University Brasov - Romania. Mr. Zainea is member of HELINA and American
Acoustical Society, being an acoustical consultant and a freelance sound
engineer. His published technical articles/papers are posted in this
site. It is listed in the Who's Who in the World & Science & Engineering
for the 1996-2009 editions and IBC - The Lifetime of Achievement One
psychoacoustical aspects when R1 is used: the sweet spot becomes
obsolete, a perceptible EDT's reduction, the masking produced by the low
frequencies is lowered, an estimated 1,5-2 dB of loudness increase. This
enhancement may be explained as a
statistical coupling of incident
and scattered waves.
1. The traditional boring sweet spot becomes obsolete. The
self adaptive bass absorption offered by the
Roundffusor1 removes the harmful dynamic masking effects
induced by the low and very low frequencies toward the right
of the audio scale. Thus small edit and control rooms filled
with our Roundffusor1 are from now on historically optimized
regarding their energy balance in all low frequency bands.
2. Effectiveness of pure tone maskers (frequency as
indicated, presented at 80 dB SPL). As you see , the 250 Hz
masker have the wider and powerful influence. The 3 tones
are presented simultaneously to the ears , and as lower the
frequency is , as much his masking is more extended, even if
at low frequencies the modes are fewer -our note ).
the masker is of a lower frequency , so much his influence
covers to the right of the audio band. If the above is valid
for tones, think about the dynamic masking imposed from
various low frequencies in a two channels spectrum from
music... Based on data of
here is the article.
The self adaptive bass absorption offered by
the R1,removes the harmful dynamic masking effects produced
by the low and very low frequencies towards the right of the
audio scale. Here is our analysis with some psychoacoustics
that the mind works like a computer, in a series of distinct stages, was
an important steppingstone in cognitive science, but it has outlived its
usefulness, concludes a new Cornell University study. Instead, the mind
should be thought of more as working the way biological organisms do: as
a dynamic continuum, cascading through shades of grey. New Cornell
University study suggests that mental processing is continuous, not like
a computer. In humans the neural activation patterns flow back and forth
to produce nonlinear, self-organized, emergent properties of a
biological organism and their resolution of the ambiguity is gradual
rather than the discrete 0 and 1; it's a dynamical system." If there was
ambiguity, the model assumed that the mind jumps the gun to one state or
the other, and if it realizes it is wrong, it then makes a correction.
Michael Spivey, a psycholinguist and associate professor of psychology
at Cornell wrote: "In thinking of cognition as working as a biological
organism does, on the other hand, you do not have to be in one state or
another like a computer, but can have values in between -- you can be
partially in one state and another, and then eventually gravitate to a
unique interpretation, as in finally recognizing a spoken word.’’
Regarding speech recognition, he argue that the older models of language
processing theorized that neural systems process words in a series of
discrete stages, the alternative model suggests that sensory input is
processed continuously so that even partial linguistic input can start
"the dynamic competition between simultaneously active representations."
We believe that listening instrumental
music doesn’t need so much ‘’brain computing’’ but when various kind of
masking are present the well known or dynamically remembered musical
patterns flow back and forth trying to ‘’put back’’ the missing (masked)
music details and, if the acoustical environment is not appropriate for
clear listening (because of too much damping / absorption or too much
reverberation), those ‘’missing parts’’ (being below the subjective /
personal perceptive threshold ) are ignored, and... gone is the
aesthetical pleasure as initially intended by the very composer -
Here below, there
are some technical , physiological, psychological, technical and
aesthetical considerations regarding a professional or a personal
session of judging a recording in an acoustically treated room - be a
recording or broadcasting studio or a room dedicated to music listening,
in a normal, Hi-Fi or High-End category.
Table 1. Parameters
examples of common
(taken from EBU Doc.Tech. 3286/10)
Examples of common
performance appears to take place in an appropriate spatial
Homogeneity of spatial sound
Reverberance - Acoustical balance -
Apparent room size - Depth perspective
- Sound colour of reverberation
reverberant / dry; Direct / indirect; Large room / small
sound image appears to have the correct and appropriate
directional distribution of sound sources
Directional balance - Stability -
Sound image width - Location accuracy
/ narrow; Precise / imprecise
details of the performance can be clearly perceived
Sound source definition - Time definition
individual sound sources appear to be properly balanced in
the general sound image
Loudness balance - Dynamic range
source too loud / too weak; Sound compressed / natural
Accurate portrayal of the different sound characteristics of
the sound source(s)
Sound colour - Sound attack
/ sharp; Dark / light; Warm / cold
Freedom from noise
Absence of various disturbing phenomena such as electrical
noise, acoustical noise, public noise, bit errors,
Perceptible / imperceptible disturbances
subjective weighted average value of the previous six
parameters taking into account the integrity* of the total
sound image and the interaction of the various parameters.
: more detailed explanations. From (EBU TECHNICAL REVIEW – September 2000 8 / 17 ,G. Spikofski
can be generally assumed that, in professional audio environments, the
"neutrality" of the listening conditions is an indispensable
requirement. However, the definition of "neutrality" is a complex issue
as the sound field in listening rooms is influenced by a variety of
parameters. In a listening room – in contrast to headphone listening,
which is determined solely by the properties of the transducer used –
the loudspeakers, the room and local relationships between the
loudspeakers and listeners interact in a complex fashion. This is true
of monophonic, stereophonic and multichannel listening.
In other words,
if one considers a conventional music transmission from a single sound
source in a concert hall, the listening experience from the reproduced
sound will be characterized by an overlapping of the "primary room
information" (i.e. from the concert hall) and the "secondary room
information" (from the listening room). Seen in
this way, "neutrality" can be defined approximately as follows: the
listening room enables the sound producer to work in a familiar "room"
environment, rather than in an unfamiliar "anechoic" environment.
The influence of the room may be just perceptible enough for the
"primary room information" not to be drowned out. "Neutral listening
conditions" are a necessary instrument for aesthetic quality assessment
in music production. In broadcasting, this is of particular importance
in the field of international programme exchanges. With the introduction
of new transmission and storage systems based on aurally-adapted data
compression, neutral listening conditions are a necessity from another
angle: only in neutral listening conditions is an objective assessment
of the quality of the new generation of audio systems possible.
Technically, the definition of "neutral listening conditions" involves
setting minimum requirements for the relevant electroacoustic and
acoustic parameters. Standards bodies have been working on the
optimization of these parameters for decades.
The typical attributes of this factor relate to sound colorations ("coloured",
"uncoloured") due to linear (frequency-dependent) distortions. This
aspect is of particular importance for the quality assessment of
listening conditions, since the general quality attributes "natural" and
"well-balanced" correlate closely with coloration.
balance: The typical attributes of tonal balance relate to
the reproduction of bass and treble frequencies. Apart from the
reproduction of bass and treble sounds ("emphasized" – "deemphasized"),
another factor to consider is the relationship between bass and treble
sounds. This becomes clear if one considers the correlations between the
attributes "treble emphasis – lacking bass" and "bass emphasis –
muffled" (in the sense of "lacking treble").
quality: The attributes relevant to interpretation of this
factor relate to the room and the (phantom) sound sources which are
simulated with the aid of stereophony in the loudspeaker base area. The
attributes "stage width" and "stage depth" describe the imaging of the
simulated sound source, e.g. an orchestra, relative to the dimensions
"spatial breadth" and "depth". Good spatial depth of the sound source is
described with attributes such as "exactly localizable", "transparent",
"detailed" and "spacious", which are contrary to the attribute
Reverberance: It can be assumed that reverberance, as a relevant
psychoacoustic factor, correlates with the sound-field parameter
"reverberation" in the listening room''.
Conditions: Listening panel
panel should be composed of listening experts, that is people who
understand and have been in trained in the agreed method of subjective
quality evaluation. These listening experts should:
work daily in the production of sound programmes of the subject genre
chosen for the evaluations or have extensive experience in listening to
sound in a professional way,
have ontologically normal hearing: ISO Standard 389  should be used
as a guideline. (Ontologically normal person: A person in a
normal state of health who at the time of testing is free from all signs
or symptoms of ear disease and from obstructing wax in the ear canal,
and who has no history of undue exposure to noise.)
be reasonably fluent in the working language of the evaluations, because
verbal expression is an important part of the method.
Explaining the ''grade'' significances, below (same source)
Very annoying defects
Too many annoying defects
A number of annoying defects
Some slightly annoying defects
Some perceptible but not annoying defects
Table 2: Impairment grades
Substantial technical defects. Unsuitable for
Should be used for transmission only in
exceptional cases. Only of documentary value.
Table 3: Qualify grades
EBU- Assessment methods for the subjective evaluation of the quality of
sound programme material- Music
You may see, that
very easy , when Roundffusor1 is used, all parameters becomes
''excellent/ no perceptible defects''. The ''Freedom of noise''
was on purpose let somehow lower, because we perceived that even in
normal , residential rooms, treated with R1, rooms not constructed as
recording studios with highly degree of sound insulation, all the above
parameters takes a ''6'' sort of the R1's unique plethora of qualities.
From : EBU – Listening conditions for the assessment of sound
programme material: Monophonic and two–channel stereophonic
- t e c h 3276
Fig1 Tolerance limits for the reverberation time
Reverberation time: Figure
1 shows the tolerance field for the reverberation time, in accordance
with EBU. The measurements are made with the used loudspeakers and with
1/3-octave band filtering. Tm is the arithmetic average of the measured
reverberation time T in the 1/3-octave bands from 200 Hz to 4 kHz. It
should lie between 0.2 and 0.4 seconds, in dependence on the room size
in order to allow a ‘natural’ spatial perception. The frequency response
for the reverberation time should be steady and continuous; sudden or
strong breaks influence the operational sound level curve. Therefore
such deviations in adjoining 1/3-octave bands in the region of 200 Hz to
8 kHz should not exceed ± 0.05s, and less than 200 Hz less than 25% of
the longest reverb time should not be exceeded.
Reverberation is the effect caused by multiple reflections
from the boundary surfaces of the listening room, which reach the
listening area after the early reflections (time delays more than about
15 ms). The reverberation field should be sufficiently diffuse over the
listening area to avoid perceptible acoustic effects such as flutter
echoes The reverberation time is an important characteristic of the
reverberation field; it is defined as the time taken for the sound to
decay to 60 dB below the initial level. It is usually measured over the
range from 5 dB to at least 25 dB below the initial value. The decay
time of the measuring instrument and the filters should be shorter than
the decay time of the reverberation field.
The reverberation time should
be measured in the listening room with 1/3rd octave filtering  using
the listening loudspeakers as the sound sources. Reverberation time is
frequency–dependent. The nominal value, Tm,
is the average of the measured reverberation times in the 1/3–octave
bands from 200 Hz to 4 kHz. The nominal reverberation time,
Tm, should lie in the range:
0.2 < Tm < 0.4 s
in dependence on the room size. To ensure that the
acoustic environment remains "natural", the value of
Tm should increase with the
size of the room. The following formula is
given as a guide:
where: V =
room volume in cubic meters
= reference room volume of 100 m3.
time T, measured in 1/3–octave bands over the frequency range
from 63 Hz to 8 kHz, should conform to the tolerance mask shown in
Fig. 1. In addition, sudden changes in reverberation time with
frequency should be avoided and the differences, T, in
reverberation times between adjacent 1/3–octave bands should not exceed
the following limits: T < 0.05 s for 200Hz < f < 8
kHz , and T< 25% of longer time for f < 200 Hz
The reverberation field should be sufficiently diffuse (linear decay)
over the listening area to avoid perceptible acoustical effects such as
Reverberation Time. The analysis of the
reverberation time RT60
in small highly damped rooms is difficult because of sparse room modes
and seldom a systematic decay as in large rooms. High RT60
is not desirable in control rooms.
Control rooms with very short RT60
were introduced in the 1960’s, but most
people find them uncomfortable and tiring when working long hours.
With multichannel or modern control rooms, the question of adequate
RT60 opens again with
direct energy and localization cues coming from all directions.
You may see that with the introduction of our Roundffusor1, the very
active diffused field produced by the R1, have a practical resemblance
with the reduced RT60 provoked by traditional absorption materials , and
we say it once again, without the harmful psychological and
physiological effect perceived from soft absorptive materials. In no way
we don't try to impose our invention by force. The remarkable results
such as indicated in this site speaks by themselves, architectural /
aesthetical considerations being over balanced by sure acoustical
EBU tech3276 recommendations :
Operational room response curve
operational room response curve is defined as the frequency response of
the sound pressure level produced by the loudspeaker /s at any listening
point. The test signal for this measurement is 1/3–octave filtered pink
noise, as specified in . The operational room response curve is an
important criterion in the evaluation of the mutual influence of the
loudspeaker and the listening room, and hence for the assessment of the
listening conditions. It corresponds well with the subjective assessment
of reproduced sound. Tolerance limits for the measured operational
response curves are given in Fig. 2.
is the mean value of the levels of the 1/3–octave
bands with centre frequencies from 200 Hz to 4 kHz. The tolerances
should be met for each (main) channel separately. For stereophonic
reproduction, the close matching of the room response of each channel is
important. Tolerance limits of the operational room response
curve. It is recommended as +/- 3 dB for 50- 2000 Hz and +3/-6 dB for
the 2000- 16000 Hz. Smoothing: 33% or 1/3 octave bands.
Fig. 2 –
Tolerance limits of the operational room response curve.
From EBU tech3276 recommendations
Measured room response curves in different listening rooms:
mean values and standard deviations in relation to
frequency. From (EBU TECHNICAL
REVIEW – September 2000 8 / 17, G. Spikofski )
ESR's case study - Fig.4 and 5. Many TEF20's (overlays) measurements (demo room
''Studioanalysis''-Athens, shown at ''STUDIOS'') made with a condenser microphone (put in the
a cardioid mode) facing in many places the walls surfaces at some 15
cm distance (the mike facing the wall's surface not the sound
source), one speaker active, on the right of the studio's console.
Please note that the spectrum's details, varies very little with the
distance or orientation relative to the loudspeaker. In this
special case study (because the room tends to a cube shape) the
ceiling and the floor were left reflective (no coverings) and the
total surface around the walls covered with small patches of soft
carpet was less than the total floor surface as recommended in
previous situations. Will be shown that even like that, the
overall TR60 was 0,4 s with no traces of echoes (TR60 in 1/3
octaves: 63 Hz=0,54s,125Hz=0,39s, 250Hz=0,39s, 500Hz=0,41s,
1000Hz=0,47s, 2000Hz=0,46s, 4000Hz=0,41s, 8000Hz=0,38s,
16000Hz=0,41s).The slop was parallel with the Schroeder's RT curves
(RT60 decay) in almost all octaves. This means, that with a
careful Roundffusor's positioning and small patches of adequate
carpet, we can let the floor and the ceiling fully reflective.
TEF20's (overlays) frequency measurements (demo
room at the ''Studioanalysis''- Athens)
Fig.5. The RT60 at the same demo
Early reverberation part analysis - Sound samples:
w1.wav(near the sound
engineer's place) and
w3.wav(room's right corner) are two recordings made in the demo
w8.wav of the same word
''best'' was recorded in the coupled rooms - hall /''A'' office. The
recordings were analyzed with the ''SpeechStation2''. Each record 0,5s,
made with a Neumann U89i, no EQ or compressor, no Effects. We compare
the content (energy/frequency) of the word's ''best'' first part (b/e)
with the syllable (st) in w1 and in w8 (office). It is obvious that the
(b/e) in w1 doesn't inject further energy and in this way the spectrum
below the (st) is clean of residual energy instead of the w8's case were
the bigger reverberation ''linked'' the parts of the word. We have to
note that even in empty with reflective walls rooms there is a partial
diffused field just that it's timbre is more than often, not nice, not
Speaking music, until now, just by listening, I believe that
the R1 are doing a kind of residual reverberation extraction from the
continuum signal/room , and not just calming the - typically speaking
-room resonances [ attenuating the musical ones not in consonance with
the direct signal ], in other words the R1 is rejecting the musical
dissonances making the atonal music sounding more like temperate/
''classical'' scales , if such an expression is permitted...
unfortunate inertia, the people prefer damped and very dumped rooms
because they didn't heard or weren't advised to hear clean diffused
sound. Almost all music halls built before around 1930 and back to the
antiquity, were diffusive and except the people and the chairs there are
no other big surfaces of absorptive materials.
Spectrogram 1 - the word ''best''- w1.wav recorded near the
sound engineer's place in the demo room
Spectrogram 2 - w8.wav of the same word ''best''
recorded in the coupled rooms - hall /''A'' office
spectrograms: with green color- the formants, with red color- the pitch
Here above we have the clear
acoustical diffusion's benefices
does the grouped R1 works ?
is so important?
When the Roundffusor1 are used as the sole room treatment
[any kind of room or music hall or cinemas], even if we remember or not the Shannon
theory of information [ where 0 means non or lost
information and 1 being the transmitted and understood
/perceived message - for us the meaning of a song's words
and context and the music's details] all room acoustical
imperfections are or tends dynamically to me corrected.
With the R1, what more than 99% of
listeners perceived is an obvious clearer sound without any
trace of any kind of echoes (echo cancellation obtained in a
purely acoustical way), the overall room time coherence
containing all the details from the source.
25-35 msec interval where the named preceding effect arrives
and makes distinct two or more reflections is ''embedded''
and masked into the diffusion field. The loudness [one of
it's definition being ''the perceived sound intensity
when we are focusing our attention towards the sound'' ]
is freely and suddenly perceived even by the hearing
impaired people. The estimated 1,5-2 units of loudness
increase is a clear explanation of R1's adaptability and a
confirmation of the diffusion superiority against the old
and too tired absorption. More, a direct result of using the
R1 is a perceptible EDT's reduction, becoming sensible
smaller then the RT60. It is known that the EDT is
considered as the subjective way for us to perceive the
character of a room along with it's reverberation (RT)
timbre and ''RT's tails'' (which for the EDT -Early Delay
Time, is a kind of RT10 ). If EDT is bigger or similar with
the true RT60, then the room's intelligibility is reduced
and along with it, and the musical details, covered by the
reverberation time's envelope.
Shorter EDTs generally
mean better communication and clearer & natural recordings,
since room falls off more quickly and masks the information
to a lesser degree. Those facts may be expressed also in
this way: ''The increase in
the scattering coefficient decreases the amplitude of early
reflections, time-smears the non-specular scattered energy,
and changes the relative balance between direct, reflected,
and reverberant energy'' (from Edge Diffraction and Surface
Scattering in Concert Halls: Physical and Perceptual
Aspects, Rendell R. Torres, Nicolas de Rycker and Mendel
Kleiner). It's exactly
what we indicated (more
than one year)
earlier, on the left diagram, our conclusions being similar
with the above ones with the addition that from a clean,
increased diffusion, the direct field's content is more
dense, real life's timbre - so no traces of coloration.
Along with the goal of a shorter EDT,
we must be able to measure some parameters
related with intelligibility and process the results into a
score (see Fig.5) that correlates with how a human listener
might judge the intelligibility. This parameters are: a) the
Speech Transmission Index or STI (the results are
processed into an intelligibility score that ranges from
zero - bad to one - excellent and b) the Percentage
Articulation Loss of Consonants (%Alcons)- positive numbers
are desirable. In all rooms treated with
Roundffusor1, the EDT was smaller than the true RT60.
At the recent International Conference of Romanian Society
of Acoustics on Sound and Vibration 2004, held in Bucharest
/ Romania , after the presentation of the three newly
corrected Radio station's studios of the State Romanian
Broadcasting Co. using our Roundffusor1, from the immediate
round table discussions, resulted once again the difference
between the actual state of the art of a practically
constructed recording studios -with the specific subjective
conclusions and the obvious inertia of strictly applying the
actual acoustical standards and interpret ting the results
analogous with the standards. And the subjective
appreciations (in our 3 cases) were enough different from
what ''should'' be the ''letter'' of some standards. In the
work presented, were shown the acoustical measurements
before and after the R1's mounting upon the acoustical
materials found there. In the R1's situation, some standards
have to be revised. Was a clear recognition, that our R1 is
a huge step forward in acoustics.
Bellow is a R1's simplified analysis (adapted
from Torres et al 2004).
Intuitively, the Huygens constructs (initially
introduced to explain light scattering)
from the whole convex / semispherical complex surface will
results in an elongated- in phase with the source-
orientated hemispherical 3D highly uniform scattering wave
lobe. Please note the coupling between each R1's back cavity
with the one below and above [the coupling between the
single Helmholtz resonator -each R1], all this in parallel
columns or rows [depending on the supports direction toward
the ground]. Thus, the horizontal diffused lobe field is at
a perpendicular angle with the resonating /filtered field
emerging from the grouped R1's complex cavity.
Sort of R1's
reduced thickness, the diffraction on the lateral wood's
supports side is very low but on the other two open sides ,
a kind of additional scattering might appear. This
scattering of diffused field
sound by the filtered
sound from the complex R1's inside one, might produce
transitional /constructive interferences related to the
frontal incident wave field which is the music- a dynamic
field. The measured phase of those two perpendicular fields
are similar and without irregularities. This, correct
in a way the known bibliography speaking about phase curve
at ''R1's critical measurements'' (at R1'1 Tests) each
vertical of mounted R1's column acts differently towards the
local eigenfrequencies. Internal R1's filtering means that
the R1's cavity self resonant frequencies interact with the
harmonics of a sound wave passing though each columns.
Basically, the result is that the harmonics from the
incident field near the resonant frequencies are enhanced,
while those away from them are damped [remember the organ
situation]. This is for a normal situation. In the R1's
case, it's adaptable filtering means that this complex
internal interaction map the musical field, correcting it in
a musical way. As the musical instruments stays such a long
time in their traditional shapes, the same for the R1 which
may be considered a musical instrument...
complex Helmholtz resonator which is formed by the back
geometry of the grouped R1 are enough similar with the air
resonances of closed-box musical instruments were all kind
of resonances play a much more active role in shaping the
sound. Air modes – resulted from resonance related to the
direct sound in the R1’s case - can have a pronounced
affect upon how acoustic energy flows through the entire
system, causing subtle changes in the volume and sustain of
the vibrations induced in the soundboard by the strings, and
ultimately, the timbre radiated to our ears.
resonating air behind the grouped R1s as the air inside a
real musical instrument has many modes of resonance, all
occurring simultaneously, all filtering and shaping the
final sound we hear. The more the space is divided up into
smaller sub-spaces, the more resonant frequencies there are,
all interacting with one another to create a complicated and
unique mixture - a musical one. That’s why the R1 are so
musical and best suited for any kind of music .
from the paper ‘’Influence of surface
scattering characteristics on the sound quality of reverberation’’
of Jacob Mueller, Mendel Kleiner, Ning Xiang, and Rendell Torres there
are some subtle results for the late reverberation, even if not as
clear, indicating that the ‘‘individual’’ sound
of scattering surfaces will influence primarily the sound quality of the
early part of the reverberation.
does the grouped R1 work ? why is so important?
This must be just another reason on why our R1 is so efficient
and subjectively performant sort of its unique shape. Seems that our
brain along with the auditory system searches the most sensitive part –
the early delay time (EDT) of the reverberation time and is searching
for pleasant or not minute tails. Inside of the named EDT, the
qualitative EDT’s content influences our senses in the first time/
moments (in fact in the first 100 msec) when we hear music, sound
generally. To be more precise for a listening room with a typical RT60 =
0.4- 0.5 seconds, the brain is immediately aware about the sound quality
from the first or dynamic time parts of maximum 100 ms (or 0,1 second)
each. All this dynamic time parts are panned in 3D and each room at a
certain moment as a sole overall EDT, a kind of room's fingerprint. A
recording, even filled with plenty of electronic reverberation contains
this ''fingerprint'' or a statistical time hologram which may be
recognized between two notes or words. Seems that the R1 ''manages'' to
make musically the link between the smaller dynamic time parts and
larger sound events scales, musically meaning the feel of natural sound,
the natural timbre.
I believe that the grouped R1's surface acts
like a double acoustical antenna, working in small/ imperceptible
fractions of time, in and out, like the ''Stargate's'' opening in
the well known and made TV serial. The R1's back interior column's
air vibration [designed to calm the room's resonances], ''dictates'' in
phase to the front diffusion surface / room's diffused field. This
complex antenna have a high gain adaptable (scattering intensity) to the
source's level/s - difficult but not impossible to demonstrate/prove (the distributed scatterer such as turbulence or,... a Gaussian distribution of the amplitude of initial field )
being -perhaps- the manifested loudness increase in the room
sensed even at 12 meters away from the R1's grouped surface.
That's why we choose a short word ''best'' to analyze some rooms.
This presumption must explain why even room off-center pair of sound
sources are perceived on room's axis with an astonishing wide image sort
of the R1's active high gain, the result - to be found everywhere in
the room, being a statistical time/frequency like hologram,
this ''particle'' information containing the stereo mix in all
We are aware that other researchers believes that combining periodical
with a-periodical geometrical shapes on their mounted acoustical
materials, the non-uniformity diffused lobes encountered in all theirs
materials having periodical shapes will be somehow minimized.
What we know for sure is, that in the Roundffusor1's case - which is a
highly symmetrical so of a periodical when grouped mounted shape, the
resulted 3D diffused lobe is at the limit of the polar plots ideal /
perfection. Analyzing in detail the Schroeder's RT curve's slopes, they
were plotted almost 99% parallel in all octaves, meaning that the sound
field was indeed being produced diffuse (highly or perfectly, as you
prefer) by the grouped R1s so the measured RT 60 or any kind of RT, was
conform with the theory.
In addition, if we
mount an R1, on both lateral walls near the listening position by
changing their heights equally, one may vary the depth and the height of
the perceived sound,
meaning controlling at will the sound stage.
This confirms, once again, that the Roundffusor1 is in a totally new
category, a giant step in the art of acoustical materials.
There are also some opinions from
academics, such as Dr. Roger Penrose of Oxford University, who argue
that brains do not work in a way comparable with a computer, so any
kind of simulation of the brain that is built on digital architecture
and uses traditional programming techniques is doomed to failure''...
does the grouped R1 work ?
I believe that our brain considers those small
parts of sound context (duration ≤ EDT and the JND - just noticeable
differences - related with all sort of differences in aural perception
resulted from some 17 cm distance between our ears) and dynamically is
comparing them with our memory - educated musically or not.
Referring to the non digital way of
working of our brain, there is no big surprise that many people really
loving hearing music keep and enlarge their LP's collection and at the
recording studio level, main path electronics are using tubes / valves
(considered ''analogues'') or software emulating old /vintage valve
gear- especially compressors.
The ''brain's'' road from 100 ms down to around 2 msec.
I spoke about he qualitative EDT’s content influences our senses in the
first time/ moments (in fact in the first 100 msec) when we hear music -
sound generally, then about
25-35 msec (milliseconds) interval where the named preceding
effect arrives and makes distinct two or more room reflections, then about the
first direct sound path of 2,5 - 3 msec from one loudspeaker to the
shortest path - supposed an observer, then about the continuum - tympanum
/ inner ear /
nerves / brain.
does the grouped R1 work ?
Here is my idea , after so many years of searching it. Why I insist so much about symmetry in the room? Like that we have a
field ''ready'' for the original field of the recording, there will be
minimal interferences between them. With the help from the R1's diffused
field, your CDs or LP or movies will sound like the original ones, with
their perfection (meaning the reality at the recording's moments and
space) or imperfections. A blend of music lovers dreams with the real
And all this, is done practically simultaneously with the
incident sound, because our hearing system cannot perceive...when. Don't
tympanum have equal air pressure above and below, the same
with R1's surface.
''when'', in my opinion is the human perception's delay. Is the time of
Summum bonum of all firings in the continuum - tympanum inner ear nerves
brain and all the (neurons or cells) firings takes some time something
under 2 msec or less..
This ''time'' depends on room dimensions and
source/s position/s. Might be considered a human constant but depends
slightly on aural human ability obtained from education or selective
listening from live or recorded music. From all musical
is predominant and this cannot be perceived so fast
because an active listening is needed and this requires an active memory
use, a comparative one. It is true that all those ''sensations'' are
synchronized in around 100 ms when ''what we hear'' is ''compared'' with
what we know and we are ''entering'' in the ''like / dislike'' moments
being ''locked'' in our brain along with the music.
Simply said- in the interval of
around 2 msec to 1 sec we begin to ''understand'' what we hear. Under
around 2 msec, we hear NOTHING.
There, inside this time of around 2 msec to 5 msec
[depending on the amount of apsorbtion installed in the room], the R1 ''manage'' to be active or
beginning to be.
sense nothing or almost nothing inside this sensorial delay.
said...real time, is not quite real time, even for sound neither for
vision... Just be happy - as me - that the R1 is...in time.
Even when we have less than half back wall (behind the loudspeakers)
covered with R1, we have an evidence that using the R1 the acoustic
field is ''forced'' to symmetry, or ... the ''expected'' wrong stereo
image becomes a wide natural well defined stereo.
In all rooms treated with R1 (even if the walls are partially
covered with initially mounted absorptive materials) are in conformity
with the EBU tech3276 & 3286
recommendations at the EXCELLENT level and beyond it. In our opinion,
what matters most is the resulted room's field timbre & sound dynamics,
music's or voice's natural pattern.
Just that being ''deaf'' for a moment
(around 2 - 5 msec) is not enough...There are some other ideas (commented
by me here) that spatial hearing is inherently non‐linear
implying that we might have to consider some nonlinear storage format,
which only helps store transients more accurately (the brain's in/out
connection with reality). From here thinking to a (perceptual)
temporal resolution of an audio system approach tending to infinite (temporally
- meaning memory not frequency domain which - resolution - is distorted
from the very tympanum - ''first sound touch''.
Also - a myriads of implication:
inherent nonlinearity in hearing (computational models of microcilia!)
used to explain difference tones, perception of harmonic/near‐harmonic
spectra, missing fundamentals - levels of pattern recognition (learned
vs. intrinsic) - comodulation of masking release and profile perception
as signs of cross frequency band processing at a low level - the
consequent refutation of strictly tonotopic place theories of pitch. A
ALL this non linearity is just another sensorial delay? Lets consider
our recording versus loudspeakers / room interface. When a pure
diffused field is created in the room then inside the sensorial
delay enters the diffusers actions. Consider and might be 99% true that
this sensorial delay is the ''real time'' ( or time ''0'' - zero ) for
our hearing. Mathematically and using the concept of quantum
mechanics (because we have a human observer /
the loudness versus timbre or spectral envelope are subdued
'beliefs', and other thoughts are again delayed
- Stapp, 1972 ), the
absorptive material is adding a zero + something (x) depending on its
surface relative to the room dimensions. Saving the World from absorption must be
define the ideal impulse perception as the one at the moment zero, then
, having absorption in the room, we get all the time a ''zero + x''
delay. We know that in music the impulse is the attack time of a note,
like the one that we hear very very near a piano or better very near to
a drum set, with just a hard played note. The more absorption we have
the more far away from the piano / drum we feel. Can we consider R1 as a
case solved within the ''mind over mater and back to the mind'' concept ? I
There is no person experiencing the R1's sound and going back to a
Non linearity in sound perception might
be considered a shifting in all parameters so keeping or succeeding a
pristine room acoustic situation helps our brain in less ''computing''
and more musical pleasure. In an absorptive environment he have
also pleasure (statistically, for the non connoisseurs) but is the
pleasure of LOW - FI ( read Low Fidelity). Be sure that a
decent Hi-Fi system sounds more musical in a proper acoustic environment
than a very expensive system in an absorptive one.
Being a real music lover is the true answer. We can sense and
pleasure the music? then we are gifted creatures..
Why I insist so much about
symmetry in the room?
Like that we have a field ''ready'' for the original field of the
recording, there will be minimal interferences between them. This
symmetry is not only a geometrical one. The R1's surface will produce a
consonant environment for your recording and room. This consonance or
unison of the musical fundamentals / octaves or their harmonics details
(exact or even approximate) are continued in our brain as neural-firing
coincidence. This is the ideal continuum interface - recording / room /
hearing and is the way a musician perceive the music. With the help from
the R1's diffused field, your CDs or LPs or movies will sound like the
original ones, with their perfection (meaning the reality at the
recording's moments and space) or imperfections. I prefer to
expose here this rough series of ideas.
Similar results and
ideas but obtained in the laboratory conditions are
Headphones listening is not exactly similar to real room music listening,
but doing such type of research in a room using two loudspeakers, is
extremely difficult. Why? Even 1 degree of head movement, change our
aural perception. Like that, the
between the subjects is broken.
Intuitively, the grouped R1 can looks like that, a finite numbers of
coupled musical tunning forks as local oscilators, as a demonstration of
wave propagation in two-dimensional arrays of scaterers. The detail, the
important detail, is in how many directions to be coupled the musical
tunning forks and the fact that in the R1's situation, we have two
layers of complex coupled forks tied together by the Janus effect.
Besides the WHEN history, we have also a HOW ones. In the project
presented below, we have a 4000 Kg of 6 ways of totally horn driven
audio system, where we designed two very low frequency of 12 meters long
double horn drivers working from 1 to 100 Hz. The whole system, using 50
R1 on the back wall and 24 R1 upon the ceiling has a resolution of
+/- 0.25 dB from 5 Hz to 20.000 Hz.
A blend of music lovers
dreams with the real high fidelity
of the page
>Important note from the PCT International
search report for our patent
1. Classification of subject matter and fields searched : IPC 7
documents considered to be relevant for this invention- the
Roundffusor1, were all in the ''A'' category [document defining the
general state of the art which is not considered to be of particular
relevance, having almost nothing in common with a previous art].
There are 3 older patents [1939,1957,1983 , with indications, where
appropriate, of the relevant passages, also, not considered to be of
particular relevance ] and a
sole paper to be open from
This indicate the almost absolute originality of our invention. The
paper is an indication of our predictions that the Roundffusor1 may be
used and as Music hall’s ceiling stage reflector or generally in big
Music Halls because is the most efficient diffuser on the market,
it's diffused field being
easily perceived at more than 12 meters from any angle.
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The Roundffusor1 may be
used in any kind of rooms
Post production studios
Quality control rooms
Press conference rooms
Film mix and dubbing stages
Music Schools & practice rooms
The unique & efficient room treatment proposal
example for a room of about 8x6x3 meters. For DO and
situations, please open the FIRST READING page from
the main menu.
Room treatments proposal
from many other international companies
color means an empty wall. In this example, about
10% from the room's total surface (including
floor) is covered with 30 grouped Roundffusor1. This
solution may be used easily in the recording studio's
control rooms. The R1's location must be regarded
in a statistical way.
The 30 or less required R1 for the 8 x 6 x 3 m situation,
may be mounted all, upon one wall's surface or only on the
ceiling surface or, as shown, in a combination of both. Of
course, the R1's advantages shown below in the
rooms, or live music rooms / halls cases are also valid.
are differences between where and how to be mounted the R1
in rooms for listening music- generally
we have to put grouped R1
only behind de speakers (mainly for electrostatic or with
any kind of back radiation speakers) or behind the listening
place or on the ceiling if not possible in the previous
places. At least 1 meter must be let between the R1's
surface and the loudspeakers.
the specific recording studios rooms,
Music Halls or TV plateau situations, rooms of any
many patches of at least 9 (nine) grouped R1 must be
periodically / symmetrically mounted if possible on all
lateral walls and sometimes on ceiling. If needed, the
loudspeakers plays with excellent results.
and grey color means various soft & hard acoustical
materials and fabrics. This is an almost 100%
walls covering instead of about 50% as the latest
research indicates and in cases when no serious room
resonance is initially predicted or measured.
are differences between where and how and to be mounted the R1 in rooms
for listening music - generally and of any dimensions, and the specific
recording studios rooms or TV plateau situations, rooms of any
1. When R1 are used, the reverberation time (RT) will be
drastically reduced whatever being the room dimensions and needs. The RT
reduction produced by clean diffusing is more important than the one
resulted from classical absorption. The RT's reduction when clean
diffusers like our R1 are used, have two main advantages: a) the
R1 is a hard, light and non porous material, not needing any further
care, and b) even for voluminous rooms as churches and especially closed
sport stadiums , the quantity / surface of R1 coverings have a
substantial reduced surface. In plus with the R1, a high level of
intelligibility is obtained corroborated with the unique low frequency
absorption, both useful for a multipurpose and voluminous hall used for
sport activity and for live amplified music. For big music halls like
sport venues, opera houses or even churches, this higher level of
intelligibility means that the people are able to understand the words,
their meaning, not just being exposed to a confuse and enough noisy
2. For recording studios rooms,
or live music rooms / halls of any dimensions for vocal or/and
instrumental performances, patches of at least 9 (nine)
grouped R1 must be periodically / symmetrically mounted if possible on
all lateral walls and sometimes on ceiling. The R1's wood supports may
be mounted vertically - for maximum low frequency filtering or
horizontally - for a softer low frequency treatment, if such effect is
needed. In special situations, using grouped/patches of R1, a
combination of supports orientation for each patch may be studied. An
homogenous musical field or, an average acoustic potential density in
the room's rectangular cross section will be obtained, both, equally
perceived by any listener or a measurement tool, everywhere in the room
treated with R1.
The room's field being homogenous and the EDT's
measured and perceived as being lower than the overall RT60 which is
already lowered by the R1's functioning, it is obvious that there is no
need for other absorptive materials. The Roundffusor1, being so active,
and periodically arranged on the wall's surfaces, dissuades the
absorptive materials (ABS)
- here is the related paper.
You may open as many microphones as you please or need.
We may read
from the (ABS)
''Much research has been performed regarding
how the size and arrangement of absorptive materials affect sound absorption.
Parkinson1 measured the absorption coefficients of absorptive materials in
different patterns and different arrangements. His experiments showed that there
is a maximum effective spacing that depends on a wavelength; longer waves appear
to have a wider spatial influence. He explained that this is mainly because of
diffraction. Sabine/2 also noticed this diffraction effect. He noted that there
is some discrepancy between what is predicted based on reverberation assumptions
and what is actually measured, and showed that a localized absorption often
produces this discrepancy due to diffraction. Chrisler/3 experimentally studied
the effect of the size of the sample on the absorption coefficient measurement.
His experiments show that the measured absorption coefficient of a small sample
is greater than the coefficient of a large sample, and the measured absorption
coefficient converges as the sample size increases''. If you expect
a comment from me, well, the diffusion phenomenon has the absorption's
apparent effects but the result is a lower reverberation time and clean sound.
The word ''appear'' said it all.
Generally we indicate a minimum of 9 or 12 Roundffusor1(for normal rooms
up to 20 square meters, this is the correct R1's number) in situations
where the user / listeners are able to discerns between differences in
sound quality. For people presenting an inertia towards deaden or
alike room treatments, or because were advised in this way, the number
of mounted R1 must be a little bigger. We encountered a situation when a
recording studio owner accustomed for many years to listen and record in
very high absorptive rooms and then, after about one week in changing to
R1 and working there, he acknowledged the benefices of sound clarity and
the huge qualitative step, easily recognizable.
Roundffusor1 - the
model ''any surface'' or portable
of you : undecided, or having peculiar residence problems or non
convinced, this is THE solution !
NOTE: this model is delivered if you still insist to keep your
older/softer acoustical treatment. Already, less and less people is asking
this ...because they understood the real R1's benefits.
for those of you decided to acquire our Roundffusor1 but [still]
intending to keep the old ''acoustical treatment surfaces'', we provide
an improved Roundffusor1 with the same geometry, material and same
external dimensions, just about 1 Kg heavier. It can be mounted - wood
framed, upon fiberglass fabrics covered, on any kind of rugose / with
asperities wall - stone wall, not plain decorative wood panels, etc., or
any kind of porous or absorptive foam materials. In this way, cannot be
acoustically influenced by the surface upon it is mounted. This model
may be used also in trade shows or professional demo rooms, or may be
sent to clients who doesn't allow that the R1 be directly mounted on the
This model doesn't need any heavy sustaining wood back
panel ! More, with the provided on demand or customer's self made wood
parts, permitting a logical and easy assembling, you may have a portable
grouped Roundffusor1's surface. As the Roundffusor1 standard, the 9 or
12 or 15 grouped portable R1 must be positioned behind the speakers or
behind the listening place, always symmetrically towards the source's
median axis. The distance between the portable R1 kit to the back wall-
just few millimeters. It may be mounted or dismantled in minutes, or if
your room permits, with some care, be entirely moved to another place.
Once you are convinced that our invention is an useful one, you mount
the R1's directly on the wall's surface, having no more acoustical room
problems, a resolute situation. And once again, don't forget that your
beloved LP's, CD's and DVD's are made in a recording studio and your
dedicated room for music must behave similarly. More and more recording
studios are made having the Roundffusor1 as a basic , not to say sole
not imitate the professionals? If this seems a commercial
trick to you, please go elsewhere...
Some conclusions resulted from R1's
Less absorption on mid and
high frequencies represents... MORE MUSIC !
First conclusion: The absorption resulted from abusive
use of soft porous materials as acoustical treatment is the unfortunate
solution of the bad sound quality in rooms, be voices or music
dedicated or both. Generally, a carpet on the floor ( not strictly
necessary ), the furniture in your room and your bodies are enough for
the required absorption.
Second conclusion: The self
adaptive bass absorption offered by the R1, removes the harmful dynamic
masking effects produced by the low and very low frequencies towards the
right of the audio scale. The R1 provides linearity for the low
frequency and clean diffusion for the mid and high frequencies, working
like an inverse ultra fast automatic wide range digital equalizer, his
power supply being the music only. These are facts easy to be perceived
and measured. The R1 may be used in any kind of room, of any geometry,
the bigger the room is, the more the diffused field is more coherent and
musical, with no difference between the live music heard in concerts and
your audio system.
Some other ideas,
may be found
here and in conclusion sounds like: ''
after all , our ears are almost similar for all of us [ statistically ]
: it is the level of your hearing health and mostly, the pleasure of
your musical education which will make the difference. R1 it is an
important cultural step helping people who loves music, any kind of
music, to return to their hobby - and not just buying expensive gear,
before is too late''...The unique solution is
here. Sound impressions in rooms were
installed : unveils more and more details in the mix, realistic sound
stage and instruments location, outstanding voice , instrument quality &
musicality, less fatigue at high levels of listening...
Third conclusion: After many R1's
installations - for normal or critical listening, the 9 or 12
Roundffusors1 mounted behind the loudspeakers or behind the listening
position are enough. But, after mounting the required R1, if you put
just one R1 on the lateral wall, in your left and right- symmetrically,
near the listening position, one may vary the depth and the height of
the perceived sound image and reverberation.
The geometrical center of the grouped Roundffusors will be the center of
the sensed height and depth of the perceived diffused field. When
mounting the R1's consider to ''tune'' your perceived diffused field in
relation with your hearing ability (if you need maximum diffused field,
the R1's geometrical center must be at your ears level ). There
must be some 1,5 - 2 meters between your listening position and the R1's
surface, the same for the loudspeakers (if R1 are mounted behind the
loudspeakers ). Why ? Because the R1's diffusion lobe may be surely
sensed at 6-8 meters and more than 12 meters for experienced people.
There is a paper
of "Diffusion" in Room Acoustics Auralization’’ by Rendell R.
Torres, Mendel Kleiner -Chalmers Room Acoustics Group, Chalmers
University of Technology and Bengt-Inge Dalenback –CATT. This paper is
analyzing the fact that ‘’ inaccurate modelling of scattering is a
remaining weakness of room acoustics auralization. Part of the reason is
that various mathematical models for scattering have not been fully
exploited and optimized for rooms. Instead, binaural room impulse
responses are currently simulated using approximate, geometrical models
and energy-based "diffusion" methods to approximate surface scattering
and diffraction. But even with these methods, one has a lack of reliable
For those of you
able to read, discern, compare and conclude, there is enough similarity
between this paper as an idea and the ‘’résumé’’ of my invention’s real
results description, all this paper being a kind of prediction
/confirmation of what MAY be possible.
Please note, the huge difference between predictions, simulations and
laboratory aural tests and the real thing in real life with clients
having their own music and own aural perceptions. I can run myself any
kind of aural test with real people, in their very rooms, with their
cheap, expensive or huge priced audio systems [see at ''STUDIOS'' - best
All the test to be
done in rooms treated with Roundffusor1, will obtain a safety 99,9%
positive acceptance. Many of my friends – all of my clients became my
friends, are telling me their own stories about how the R1 helped them
to re-gain and re-enjoy the almost lost music listening pleasure
[selling, buying or exchanging the audio gear, without fixing the room
And don’t forget
that real music begin there were the recording is made, continue in each
ones real , specific room [ now treated with R1] , specific room being
‘’driven’’ by specific loudspeakers, which speakers plays as low as
15-or 17 Hz or even lower for some subwoofers [ computer simulation
''stops'' at some 125 Hz ]. The lower frequencies the loudspeakers
plays, so lower and even lower than that, the very room ‘’play’’ also –
in the named ‘’infrasound’’ zone. There is no way to solve
simultaneously all this problems with the acoustical materials designed
Learning about our USEFUL SOLUTION - The Roundffusor1, probably you
understood that it is working adaptively down to some 5 Hz, so your room
treated with R1, are SAFE for all spectral situations and for all kind
of audio systems – from the cheapest to the most expensive ones. I've
designed the velvet like covered R1 just to solve the horn speakers
directivity problem. Please bear in mind that all kind of electrostatic
speakers needs unconditionally that the wall behind them have be covered
with R1 , on a surface, geometrically, similar with the surface ''seen''
by the loudspeakers, from their left to the right. The wider the
distance between those loudspeakers , so much the surface covered with
R1 on the back wall, behind the loudspeakers.
At some Forums on the Internet, a wide
and open discussion opened around R1. Many people tends to understand
part of the explanations given here and some ( for strange reasons )
asks for more. We don't use paid articles or virtual results. All this
site - regarding the R1- is just a continuous description of what really
does the R1. The R1 is an adaptable low and very low frequency absorber
so for this thing , each measurement is specific to a specific room
geometry / number of mounted R1 and the kind/position and quality of the
audio system. So the absorption curves will be each time a specific
measurement not possible to be indicated for another setup, even
Even the ''old design'' of materials dealing with
low frequencies doesn't behave the same in different conditions. The R1
works to near perfection only grouped mounted, so the bigger the room
the more R1 you need, just for one wall (usually). Because the R1 works
grouped, their empty column's linear dimensions are a whole or a
fraction of the wavelengths of the spectral source and the air inside
each columns resonate accordingly to the source spectrum and energy, a
dynamic situation. There are complex phenomenon between the R1's back Helmholtz resonator function and the very active frontal diffusion one.
Special and sophisticated mathematics or practical and superb results ?
In 1970 Alvin Toffler, noted technologist and futurist, argued that the
acceleration of technological and social change was likely to challenge
the capacity of both individuals and institutions to understand and to
adapt to it. ... Our ability to handle simultaneous complexity is
governed by what cognitive scientists call "fluid intelligence,"
commonly defined as the ability to find meaning in confusion and to
solve new problems. But this process will inevitably have limits.
Eventually, we'll hit a ceiling in the ways in which we can improve our
fluid intelligence naturally. At that point, we'll face a hard choice:
make major changes to our work and social cultures, so as to reduce the
degree of simultaneous attention-grabbing activity; or develop
augmentation systems that enhance our natural fluid intelligence by
recognizing, from moment to moment, what needs our actual focus, and
what can be handled by proxies. The wise choice would be the first one.
It should come as no surprise, then, that I suspect that we'll do the
second (from Open the future by Jamais Cascio ) or, with enough minds,
all tomorrows are visible.
With the Roundffusor1 many acoustical ''squared ideas'' becomes
obsolete. Why not put the loudspeakers half way between listening
position and the opposite wall ? In this area the direct and the
reverberant field are somehow blended. In real life, in a
''spark'' of 25-100 millisecond what is going to happen will happen.
It is the time that our ( experimented and perhaps educated) hearing
system ''concludes'' and we understand the sense and meaning of those precious words
defining the sound quality. If this audio field is not a pleasant one,
nothing will save you - even the most expensive gear , but the acoustics
and ONLY the Roundffusor1! In applied acoustics, this ONLY is rare...
BE CAREFUL :
THE ROUNDFFUSOR1 IS NOT A SOUND INSULATION MATERIAL
By < sound insulation
> we understand to not disturb our neighbors or be disturbed by them –
this being ‘’performed’’ by putting between ‘’us’’ and ‘’them’’ enough
‘’concrete’’ distance, meaning one or more parallel solid walls or much
wider ‘’patched’’ porous materials, but wide is anything more than 1-2
meters or more in order to attenuate AND the low frequency
disturbance. Even technically educated people confuse interior room
acoustics with sound insulation. To be precise, if you
mismatch the porous ‘’sound insulation’’ with ‘’room acoustics’’ the
‘’best’’ result will be an insufficient sound insulation and a very bad
quality room’s sound field – a muddy and without clear / natural
midrange and high frequency spectrum, I repeat – IN THE ROOM.
The Roundffusor1 introduces a new concept
INTERIOR ARCHITECTURE OR SIMPLER ROOM DESIGN
This means that your listening or home cinema room doesn't need to
look like a recording studio or an architecturally, aesthetically &
heavy absorption charged villa's suite, which may be the road to indulge
yourselves in a little bit or more luxury, but surely not the way to the
Roundffusor1's mounting instructions
How to integrate the Roundffusor1 into
a typical false ceiling
An example for a matrix of 3 x 3
R1's, meaning 9 ROUNDFFUSOR1. We have 4 parallel wood rails / supports,
for 3 rows of Roundffusors. Each wood support is 58 x 3 = 174 cm long.
Each diffuser is mounted upon 2 lateral supports, and all diffusers are
mounted in parallel rows, vertically or horizontally relative to the
floor, if to be put on the back wall. You need 1 screw for each, meaning
2 screws / Roundffusor1.
But each second support
is common for 3 neighbor diffusers - because they are mounted in
rows, so in fact 3 diffusers in a row, needs only 6 screws, 6 diffusers
needs 9 screws and all 9 needs, you guess, only 12 screws. If you want
to be more secure, you put more screws. If mounted on a wood surface,
nails, are enough. Maybe you think '' big'' , but each wood rail is a
section of [30x30 mm, of a ''T'' profile] and some 174 cm long for rows
of 3 Roundffusors.
All 9 Roundffusors standard weights
only 9 x 2 Kg= 18 Kg, so no need to worry about. The way they are
mounted makes them to behave like very heavy plastic, so no resonance
will results, if you are afraid of it, and NO SOUND COLORATION.
Generally, for rooms of less than 25 square meters, the nine or twelve
Roundffusors on the back wall - opposite to the loudspeakers place, or
just behind the speakers, are enough for a first good impression.
we made listening tests some 10 years ago on scale model diffusers which
showed that spherical diffusers were superior in sound quality '' PhD M.
Kleiner, Professor - Director, Program in Architectural Acoustics School
of Architecture Rensselaer Polytechnic Institute , Director, Chalmers
Room Acoustics Group School of Civil and Environmental Engineering
Chalmers University of Technology, Gothenburg, Sweden.
and my friend from Russia said : ''Dear Zainea, Thanks for your
message of 22 August 2002. You seem to do very interesting and important
practical work in acoustics. In spite of I am more theoretician, I can
feel the key essence and advantage of what you have already achieved in
your research. ‘’ Russian Professor M. A. Sumbatyan
In simple words it cleans the lower
and diffuses the higher frequencies and the result is fantastic music. I
have installed 15 pieces in my room and still
I can’t believe the performance and the change that have been occurred''.
A distinguished Greek private client
Congratulations for the advertisement, the R1 is the best. The 5X3 R1 is
at last on the wall. The effect is wonderful. The nasal sound
disappeared because of which I could not increase the volume of the
sound up till now. The room is quieter; I can listen loudly and softly
too without having anything disturbing. The walls disappeared. A lot of
information emerged which I have not heard yet. The sound picture is
more colour, it received life. The starting and stopping of the voice of
the instruments is real now. The beginning and the end of the bass is
correct at last, it does not running around the room. Everything is on
the right place. A miracle happened. Congratulations. I will send you
the pictures. Best regards, Sándor''. From Tamás Sandor, owner and State
Hungarian Philharmonic member, Double Reed Co.
Magazine on line:
Acoustic materials 2005-guide to new
professional acoustic materials for the studio
published, independent tests, interviews, all in Greek
'Hxos-Eikona'': R1's Test
AV Pro's article: R1's Test
Radio-Link's article: R1's Test
Radio-Link - Zainea Liviu Interview
United States Patent 7,261,182
- Zainea Liviu Nikolae.
Wide band sound diffuser with self regulated low frequency absorption
and methods of mounting
Zainea Liviu at the
University of Patra / Greece - The Roundffusor's presentation
many audio dealers will
you that A and B are different colors ...
with Roundffusor1 you
the difference between electronics...
in fact, A and B are
of the same color (5)
so, where is the truth ? little
Music: The Art of Listening
Mr. Zainea Liviu Nikolae / ESR, 14 Peresiadou
street, TK11141 Athens, Greece
0030 210 20 27 191
0030 693 66 07 321