The acoustics of a room are largely determined by its geometry and the properties of its surfaces.
Every room has its own sound. Depending on the proportions and properties of the room, this room sound can vary between “dry” and “echoey”, and between “indoors” and “outdoors” - although it is hard to describe the sound of a room with terms like these (just like with numerical values).
Purpose and interior acoustics
There is a wide range of requirements in room acoustics. A recording of the spoken word should generally be relatively free of influence from the room, but with recordings of classical music the acoustic effects of a “large hall” may actually be desired. A measuring station on the other hand poses other requirements than those of a recording room.
Depending on how the sound is generated (speaking voice, singing, musical instrument, noises, etc.), on an individual’s hearing and on the type of any processing (sound recording, hearing test, measuring analysis), different sound characteristics will be desired and indeed necessary.
Individual room sound
Owing to the very varied range of uses, it does not usually make much sense to have room acoustics “off the shelf” – only in rare cases is a reduction to two or three “standard items” sufficient to adapt the interior acoustics to the physical situation and the individual needs of the users.
An effective approach to this sensitive topic can only be brought about by the individual adaptability of the room’s sound.
Room acoustics and influencing factors
The curves show how the different absorbabilities of various acoustic elements and materials vary with the frequency f.
The type, arrangement and number of the acoustic modules used in a room result in different reverberation times with varying distributions of room modes and intensities.
The following graphs show some results obtained using various claddings with different acoustic elements. Deciding which elements will finally be used for the lining depends on the level of sound absorption that is required and desired.
Reverberation times with surface absorbers AKM
Acoustic cladding AKM (“surface absorbers”) of the type “Pyramid” absorbs higher frequencies most of all.
The way such cladding influences the reverberation times is shown in the graph below:
Reverberation time with wedge absorbers KAB
The use of KAB wedge absorbers has most effect on the medium and low frequencies.
The way these wedge absorbers influence the reverberation times is shown in the graph below:
Reverberation time with block absorbers BAB
The use of BAB block absorbers has most effect on the medium and low frequencies.
The way these block absorbers influence reverberation times is shown in the graph below: