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      Ultrasound      

 

Acoustic design

 

 

Summary

 

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Foreword

In normal domestic situations, very often the main limit to the quality of the reproduced music is represented by acoustic environment. If - for instance - a big and famous orchestra playing in a football stadium (or any other place of inadequate acoustic characteristics) seems to everybody an heresy, it is nevertheless common practice to place HIFI systems in inadequate environments, attributing the insufficiency of the result to the low quality of the components. In the same way, driving a Ferrari on a country road you could decide it's a bad car; but if you try it in proper conditions, the conclusions are reversed. It makes therefore no sense spending a lot of money for the acquisition of sophisticated components without the chance of using them adequately: that is, without installing them in correct acoustical conditions.

To this purpose, one can find on the market some devices to correct the acoustics; they normally come with instructions on their positioning. This type of intervention, even if effective, has the big limit of a general purpose solution: it is based upon a model of propagation of the waves that is a semplification of reality, and for this reason the results could not be as good as espected.

The real solution is the direct measure of the acoustic parameters of the room; in this way, we eliminate uncertainty connected with theoretical simulations on models simplified of the reality. Moreover, the visual examination of the environment allows underlining of speci al cases bring to a solution tuned up to the room also from an architectural and aesthetical point of view. All that could be gotten from an experienced professional.

Our engineering office deals with acoustics from 1988 (in civic and industrial); we have accumulated big experience in acoustic correction, with particular attention to the small dimension environments. The domestic rooms, in fact, with typical measures lower than 10 meters, present accumulations of energy in the low-middle frequencies, with often a too much elevated absorption in the middle-high range due to the presence of the normal furnishing. This situation is substantially different from what normally can be ecountered in the musical acoustics (auditorium, theaters, etc.), so the experiences and the simulation software normally used in those situations is poorly effective; moreover, the available surfaces to install the correction systems are generally small, so that inserting "general purpose" devices is often very difficult (regardless of aesthetical aspects).

 

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Specific solutions

Here you are a small panoramic of the suggested acoustic corrections in domestic environments, divided according to the type of desired correction:

 

CORRECTIONS IN WOOD

In the almost totality of the cases the furnishing is based on wooden furniture; if the same is used to realize the devices of acoustic correction, we can get not only substantial improvement in sound, but also an aesthetical enhancement of the environment. We can indicate three different ways:

building resonators able to modify the low-middle frequencies absorption. In this way we could get a better absorption (more or less selective), and a different distribution of the acoustic energy inside the room;
   
installing vibrating panels able to transform the sound waves in mechanical vibrations;
   
building structures able to modify the paths of the pressure waves, we can achieve a more uniform distribution of the energy and, controlling the reflections, a virtual increase of the dimensions of the room.

 

 

 

CORRECTIONS WITH FURNISHING ELEMENTS

An opportune drapery, according to the type of fabric and of his installation (above all the distance from the wall) could become a fairly selective absorber; stratifying the draperies we could get absorptions until to 95% on a wide range of frequencies;
   
carpets, armchairs, furniture, etc. could be added, eliminated or moved to get the wanted absorption.

 

 

Using the indicated techniques, environments with exceptional characteristics could be gotten, both in the frequency domain (th at is, without accumulations of energy in particular bands) and in the time domain. To this last aspect, with an optimal planning it is possible to continue to identify a transitory signal when his level has decreased of 50 dB (performance that few audito riums could boast), when in a normal environment hardly the transitory is distinguishable beyond the 10 dB of attenuation (with the commercial treatments it\rquote s hard to surpass 20 dB). That means to appreciate all the low-level details that make the music fin ally alive, with a perception of the tones and of the ambience otherwise impossible. In an environment of this type, everything becomes evident: the difference between a component and the other become enormous, any single modification in the chain could c hange radically the sound of it.

 

WITHOUT A CORRECT ENVIRONMENTAL ACOUSTICS

THERE IS NO GOOD SOUND!

 

Contact us and we will study together the best solution for you:

049 8644085

 

Ultrasound
Vicolo T. Aspetti, 18
35100 Padova (ITALY)
Tel./Fax: +39 049 8644085

Showroom
Via Bachelet, 20
Busa di Vigonza (PD)
Tel.: 049 8935095

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