Working Group
1.73
Room Acoustics
a-Databank
The most important requirement for a
successfull simulation of room acoustic parameters with computer simulation programs is
the knowledge of the exact room geometry and above all of the reflection properties
of room limiting surfaces. To give the user and developer in this special field a uniform
basis for the last mentioned parameters PTB working group 1.73 initiated a data collection as EXCEL-file and as compressed zip-file. It will be kept up to date.
All absorption grades (a ) and - if possible - scattering coefficients (s)
known to us are listed and can be downloaded and used as you like. To simulate the
reflection properties of sound waves on walls these data are (mostly) needed in octave
sectors by room simulation programs. At present more than 2000 data
sets are available (approx. 1.85MB).
In case you know further material properties
not yet included in the table we would appreciate to let us know the data and the
reference. If you notice mistakes or if you would like to assign other data to a certain
material as listed please don't keep back with criticism. This table is intended to serve
the room acoustician with uniform data!
Recommendation for use:
The user can sort the data with Excel functions by selected criteria: some columns contain
functions that deliver interesting criteria for sorting. E.g. fMax
contains the octav centre frequency of the maximum value of absorption. This value is
displayed in the column a max. Sorting
procedure: Choose sheet "selection_table". In columns AK
to AW choose criteria according to shown legend. Click on an arrow and then on your chosen
code-nr.. Click on button "selection". Sheet "graph" opens and you can
take a look at the chosen data by clicking on button "selected data". Further
sorting procedures according to the first one are possible. You leave the selection by
clicking on button "selection off" . Button "entire data" is available
again. Further you can choose "user definable" and define one or more conditions
that your problem requires: e.g. fMax = 1000 Hz, or a max < 0.8.
Besides reference
data for private studies are available. By means of
these data simulations can be calculated. The given room is
the PTB studio without features. It will be completed gradually
by real detailed structures. Because of that a control of results is possible from the
most simple model to the complete real room.
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