AcAna_a week of analisys

During this first week of analisys, me and G.Bianchi attempted to understand wheter the software we use is able to analize a particular shape configuration, giving a precise result.

This verify is necessary for two reasons: 1) RAMSETE software uses a piramyd tracing system, which we didn't know yet if it approximates the sound as quanta of enenergy or if it considers its wawy nature (we need indeed this second form of analisys). 2) it's the very first time for bianchi to use this software, since the other ray-tracing softwares don't consinder the sound as a wave.

To sort these results out, we've been making the analisys of different objects in the same ambient, with the same source. More precilesy,

  • An ambient without furniture (it's a standard room 20 sqm per 2,7m heigh), with a dodecaeral (omnidirectional) source in the corner.
  • We put in the opposite corner a simplified component without the caracteristic RPG shape + furniture
  • The component with a fully drawn RPG, designed for the range of frequencies 800-6000 Hz (whose effects are well known to bianchi who designed and relised it prevously)

As result, even tough the pyramide tracing do not approzimates the sound like quanta, we discovered that the it is not able to evaluate a singular configurations. I've collected and publish the informations of a receiver point, located in the exactly same point in tha chair.

Indeed, there is an high difference between the empty room and the furniture-full one. We expected this, as we expected the lowering of both the T10 (we put in the room absorbing material) and the Leq (due to the smaller quantity of energy bouncing in the room),in the furniture case. Since more energy is absorbed, we find a rising in the Definion, while the Clarity moves away from values we defined good (which means that our component is not goodyet). We conclude that the software is working.

On the other end, Values for the RPG are far from what we expected: they're too similar to the empty situation (we don't know why), even tough the furniture is absorbant. But also, there is no significant changing in values in the frequencies range 1000-4000 Hz from the other. This is not possible, because the RPG is designed to diffuse frequencies between 800 and 6000Hz.We conclude that it is not possible to work in this way.

There is another way to work these analisys, it's about the use of a recently discovered coefficent of scattering, which evaluates the sound diffusion.


This coefficient is an innovation for the normatives: for this we know neither how to use it properly (it will take some trial to sort this out) nor if it can be an accurate instrument of testing. In any case, we will start this new phase of the analisys after christmas.


Office spreadsheet icon AcAna_results.xls68.5 KB


At last, me and G.Bianchi succeded to make the software analize the problem.

Even tough it will be necessary to understand how to use it the best, it is possible to work on the scattering coefficent and seek the component's configuration.

I'll publish soon the results of this important step forward.



Happy new year