Recording studios

R1 in simple words

Roundffusor1 theory
Low frequency-Why?
R1's Tests
High - End
Ideas & Sound
How to buy R1


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Practical acoustical Do / Don't explanations

With the R1 you have clean and clear sound, full dynamics, no booming, real life wide sound stage, no sound coloration !

The sound that you hear in any room is more or less 60 to 40 % REAL room acoustics


40 to 60% your audio system !





When and How does the grouped R1 work ? Why is so important to know ?

Why the absorption is so...harmful for the music perception?


For recording studios rooms, or live music rooms of any dimension for vocal or/and instrumental performances, patches of at least 6-9 grouped R1 must be mounted if possible on all lateral walls and sometimes on ceiling. An homogenous musical field will be obtained. You may open as many microphones as you please or need.

- the loudspeakers 


In most situations, you don't need to put any R1 on the ceiling...

In this two typical situations, the rooms are identical but the quality level of acoustics is not.


If you like the R1' geometry / aesthetics don't use any other absorptive materials with or around the R1.

There is absolutely no need to fill the R1 with porous materials. You will reduce the R1's complex functioning. Doing this you will pay to destroy your sound...

Don't try to cover the R1 even with the most thin loudspeaker's fabric. You will destroy its amazing diffusing capability.

>> An example not to be followed <<

In both pictures white color means an empty / not covered wall.

For normal rooms - dedicated to music listening or control rooms in recording studios of about 15-24 square meters, 9 to 15 R1 are enough, to be mounted grouped behind the loudspeakers, or on the wall behind the listening place or just on the ceiling, always strictly symmetrically towards the sound sources median axis.

For bigger rooms / music halls, generally, the number representing the floor area in square meters is the maximum number of necessary R1,both for ceiling and one wall treatment.

It is important that the listening room not to have major openings because the adjacent rooms-named coupled rooms enhances and disturbs the timbre and reverberation time of the main room.

In this example, for a room of 8x6x3m, about 10 % from the room's total surface (including floor) is covered with 30 grouped Roundffusor1. For a room of this size, a carpet on the floor might be needed. Please note , that this room have no major openings.

 Mount the grouped R1 beginning at 60-90 cm relative to the floor, above the power outlets and various connection's zone. Always a 5-10 cm space must be let free at the two R1's open edges in order to let the devices working as complex Helmholtz resonators.  

In a room treated with R1, you need no equalization at all. 

  Nothing being white, this is the worst situation where a room is totally covered with materials - absorptive or not. Please note , that both rooms shown here have no major openings. Speech intelligibility in such a room is hard to be optimized. In a room like that, it is impossible not to use complicated  equalization, not compatible from song to song and/or different music styles. 

Why not materials like ''bass traps'' ?

How does the Roundffusor compare to a dedicated bass absorber? Some types of bass absorbers are "tuned" to a particular frequency. While this method can be  effective for industrial purposes, in our experience it is not a good way to tune the bass response of a listening room because the effect can be somewhat unnatural.

The Roundffusor offers a milder, wide-bandwidth (low-Q) type of absorption which is similiar to the sound of a "flexible wall" bass absorber. Unlike a custom-built soft-wall, membrane, foam, or fiberglass absorber, the Roundffusor is more adaptable (by extending the column length) and movable. Because of the large surface area and the wide bandwidth of the R1's bass absorption, the resulting sound is an improvement over a very wide range of listening positions and frequencies. Subjectively, this results in a truly dramatic improvement compared to a conventional bass absorber. The fact that the Roundffusor1 does not absorb high frequencies, but diffuses them throughout the room instead, means that the spectral decay (often measured as the RT60) will stay even from the bass to the treble range.


The smallest recording studio's vocal booth treated with the R1 was 2.5m length x 1.5m width x 2.5 m height. Needless to say, the voice- in the booth and recorded, became suddenly naturally and clear.   

The R1 reduces the overall room's reverberation time (RT60) as would do a much bigger typical absorptive surface. With R1 you have no porous materials in your room. All kind of porous materials may be a problem for your health. 

  The low frequencies are responsible for poor communication, difficult ensemble playing, for increasing hearing loss in musicians and the harmful masking phenomena. Using the R1 you don't need any kind of the said ''bass traps'', because all the bass filtering is made inside the R1's columns.

Please see the R1's critical measurements

The R1 It's not a sound insulation material !     Don't install R1 on the lateral walls when frontal loudspeakers are used. The sound image will be optimized by the front or back grouped mounted R1's.  
With the R1 you have clean and clear sound, full dynamics, no booming, real life wide sound stage, no sound coloration !

The sound that you hear in any room is more or less 60 to 40 % REAL room acoustics and 40 to 60% your audio system !

  As with the all unique things in this world, there is only one shape and a plethora of advantages. Don't try to use the R1 as you please ! The professional world is using the Roundffusor1 the way the R1's inventor advises you in each situation.   Free of charge.



Architectural acoustics? It seems simple but wasn't until now ! Why? Do you have clean and clear sound, full dynamics, no booming, real life wide sound stage, no coloration? All this must be fulfilled simultaneously! It is hard to believe that this is easy to be found, so, the Roundffusor1 is the unique, patented answer.

The R1-the standard or the ''any surface/portable model'', will bring your recording & mixing sessions and your live acoustic performances there where you always dreamed-to the naturally perceived sound . 

For normal rooms, of about 15-24 square meters, 9 or 24 R1 are enough, to be grouped mounted behind the loudspeakers, or on the wall behind the listening place or just on the ceiling, always strictly symmetrically towards the sound sources median axis, and... there is no need to install R1 on the lateral walls.

Warning !!! In rooms almost or really of a cube shape , the R1 must be mounted on the ceiling and one wall - behind the speakers [if the loudspeakers are dipole or electrostatic , in order to support their back sound radiation] and maybe a carpet will be required. The R1 is bringing your musical source/s in harmony /consonance with the room's field - meaning with a timbre with musicality, smoothing to inaudibility all nasty room resonances. The number of R1 required for such a cubical shape rooms, depends on their volume. A simple rule, is that the number representing the floor area in square meters is the overall number of necessary R1, both for ceiling and one wall treatment. For example if your room have a floor surface of 5 m x 5m = 25 m2, then less than 25 units R1 will be needed, 12 on one wall and 12 on the ceiling. In such rooms you also can try the ''corner mounting'' solution, in two adjacent corners behind the speakers or for all 4 corners.


In much smaller rooms, as the one used as speech cabin radio announcements, you have to play with the wood supports orientation in order to calm down the annoying resonances, the smaller the room the more perceptive are the room resonances. In such a rooms if filled with absorption materials, the voices becomes dull and blurred, the microphone is taking the stronger room resonances - even fewer [a mix of low frequencies and subsonic harmonics], above the timber's voice. In such situations, with rooms built in the traditional way of using everywhere absorptive materials, it will be wise to ask the newscaster if he or she, without knowing enough well the text, will be able to understand his/her own voice. Using the R1 in small patches upon all walls and part of ceiling, and a simple carpet on the floor, believe it or not, you have the solution of voice clarity.

Time to mount 9 or 12 R1's along with the provided wood drivers using simple home tools-about one hour!

The low frequencies are responsible for poor communication, difficult ensemble playing, for increasing hearing loss in musicians and the harmful masking phenomena. You surely know, the low frequencies excess's and the standing waves problems are common in almost any room. In order to smooth them and calm you, we successfully opted for a very large aperture complex Helmholtz resonator with indeed minimum flow resistance using no porous material.

The low frequency resonator and the full range clean sound diffuser is the one and only sole full audio band device, working efficiently from about 5 Hz to the high frequency limit of our hearing ability, the R1!  Don't expect to play bad recordings and hear absolute quality sound. The R1 will unveils your recording problems along with your environment specifications. 

Luxury built rooms let you with the same mediocre sound after few days of visual admiration. You don't know precisely why you spent so much for your audio installation and in your room the sound is not as expected. There is a lot of people giving you free or expensive advices and you are still unhappy with your sound. 

All this, for most professionals or a hobbyist must be already understood but it isn't. Why? Because if  just a few small details are forgotten something happens and the sound is not good as expected.

Maybe all this that you are reading seems too much, or even unbelievable. The whole idea behind a revolutionary invention like the R1 is just this, a big challenge.  

Don't try to measure just one R1, but at least 9 units in a 3x3 matrix well mounted on a hard and steady surface.

It works and must be measured grouped in at least 9 units matrix. The more grouped R1 are you acoustically measuring (by yourself or in a qualified acoustical laboratory), the more the standing waves are able to be smoothed by the R1 and the diffused field characteristics are almost identical to the ideal diffusion curves. Please note that, the more R1 are you measuring, the reverberation time is perceived and measured as lowering accordingly, the musicality of sound being the most acknowledged aspect.

As the practice and theory said, If the sound source is positioned as away as possible from the R1’s grouped surface, a much powerful, clean and containing all the source information becomes the diffused sound field. Contrary to the other materials which are used in a more architecturally / decoratively way rather than with pure acoustical parameters in mind, try to imagine the aural result from a large Roundffusor1’s covered surface in a big hall…

More and the most important, the grouped R1 works - as the human hearing and musically as the musical instruments - from the normal voice level ( 55-65 dB ) up to more than 130 dB SPL. There are no other materials really active at such extreme levels and keeping the source quality throughout...

Fortunately, we are in one of the rare situations when objective acoustical measurements tends to approve the subjective  / perceptive ones or vice versa.

Using R1, you may perceive for yourselves that for the home cinema situation , all the frontal source information are transmitted and spread naturally , like in real life, towards the back of your room and the many satellite speakers for some, becomes redundant. The research indicated statistically, a tendency for a very good stereo plus central speakers situation instead of many and from time to time wrong calibrated lateral speakers. As all things in life, statistic may be a subjective matter. Using R1 in home cinema rooms is a bright idea.

The clean R1's diffusion's result?   It's like being immersed in the initial recording room along with the electronically or naturally recorded reverberation times. In the recording sessions, the R1's keeps the original timbre & dynamics for all kind of instruments and voices. Aesthetically, what's better than the original?  

Here are the R1's critical measurements, 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 - adaptable for low and very low frequencies, up to 181 Hz and beyond this, the mid and high frequencies are drastically damped [ only from the R1's inside ] 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.

There is absolutely no need to fill the R1 with porous materials. Who insists in this , in fact doesn't understand the R1's functioning....

The R1 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 deeper ‘’patched’’ porous materials, but ''deep'' is anything more than 1 - 2 meters or more in order to attenuate AND the low frequency disturbance. Even some technically educated people confuse interior room acoustics with sound insulation.  To be more precise, if you mismatch the porous ‘’sound insulation’’ with ‘’room acoustics’’ the ‘’best’’ results will be an insufficient sound insulation and a very bad quality room’s sound field – a muddy and without a clear midrange and high frequency spectrum , I repeat – Inside the ROOM.

Using the R1, a drastically Reverberation Time lowering is obtained !

And this not by absorption but... Using clean diffusion

This means much better intelligibility...

The Roundffusor1 is the World's most efficient acoustical diffuser and self adaptable low frequency absorber. Self adaptable means that our device filters, from case to case, the undesirable room responses and lets your preferred music sound as it was recorded.

As the R1 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 centimeters.    

And once again, don't forget that your beloved LP's, CD's and DVD's are made in a recording studio or a music hall 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 acoustical material. Why not imitate the professionals? What is a really good sound is another story but usually, live acoustic instrumental & vocal music, may be the reference. If your sound system cannot reproduce close enough-at realistic levels or not, just one instrument as heard occasionally played in the street, then you have a problem, usually an acoustical one. Once you have had bought many sound systems or improved them continuously and you are unhappy, then your room is not acoustically treated or is wrong treated and you loose ''somewhere'' parts from your music...

The R1 may be used  in Hi-Fi, High-End rooms, home cinema, music schools, churches, recording and rehearsal studios, TV studios, music halls and big multi channels sound cinema halls.

The R1 is a hard impact polystyrene made device. You mount it in your dedicated room for music, just on one wall or ceiling and instantly, you obtain Perfect Acoustics.

Additionally, the R1 reduces the overall room's reverberation time (RT) as would do a much bigger typical expensive absorptive surface.

The typical absorptive materials are any kind of porous materials or combination of porous, fabrics and hard materials covered with fabrics, those materials producing absorption in the mid and high frequencies, there , where the music's details should always be heard. Don't forget that all porous materials may be a problem for your health. 

Are you aware about this wrong and inertial situation ? It is a problem for you ? 

The R1 reduces the room's reverberation time [RT] and you will perceive the sound in your room as if the room is filled with a lot of furniture, heavy curtains, etc. and in fact being empty, with just a carpet on the floor or even without it - a thrilling experience.  This RT's attenuation offered by the R1- a smooth and musical decay, is adaptively correlated with the sound contents- live or recorded and the very specific room dimensions.  

All this are the R1's diffusion useful role

a smart alternative to the so tired and harmful known typical absorption...

This idea about really clean diffusion's role, is more than 70 years old one!


The Roundffusor1's paper

The Swiss Invention Network collaboration


Company address 

Mr. Zainea Liviu Nikolae / ESR, 14 Peresiadou street, TK11141 Athens, Greece    

Communications data

Tel/Fax: 0030 210 20 27 191   Mobile: 0030 693 66 07 321


Skype: zainea.liviu

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