Auditoriums

The 2nd Round Robin on Room Acoustical Computer Simulations was made in the Elmia Concert Hall in 2000. The demo shows the agreement beween measurements and simulations made in ODEON 9.1. A concert halls is one type of auditorium. Other auditorium cases could be churches, mosques, opera halls, lecture halls or music studios. See below the example for ODEON features.

[1] A grid responce of Reverberation time at 1kHz with 1300 receiver positions.
[2] Measurements were simulated in 12 source-receiver pairs – here we are looking from each receiver position at each source as well as having a look around the room.nt scenarios and have a group of architects, engineers and future users evaluate the acoustic qualities in different zones and in-between the zones.
[3] Wireframe of the Elmia hall, displaying source and receiver positions.
[4] Source 1 active. Examples of simulated room acoustic parameters compared to the real measured values. Majority of simulations are closer than 1 Just Noticable Difference (jnd) to the measurements.
[5] Source 2 active. Examples of simulated room acoustic parameters compared to the real measured values. Majority of simulations are closer than 1 Just Noticable Difference (jnd) to the measurements.
[6] As can be seen from previous slides, ODEON does a nice work in predicting room acoustics – at leisure time it plays billiard!

ODEON features for auditorium acoustics

FeaturesBenefits
Simulation of reverberation time measurements in selected positions as in ISO 3382The reverberation time is calculated from the squared impulse response method
Room acoustic parameters according to ISO 3382 are calculatedObjective descriptors of the following listener aspects: level of sound, reverberance, clarity of sound, apparent source width, and listener envelopment
Stage parameters according to ISO 3382 are calculatedUsed for characterising the ensemble conditions and the perceived reverberance for musicians on the stage
Calculated STI (Speech Transmission Index)Objective descriptor of the speech intelligibility in a listener position taking the reverberation and background noise into account
Global reverberation time estimateVery fast and accurate, takes into account the room geometry and the distribution of absorption materials and surface scattering
Mapping of room acoustic parameters in gridsOverview of sound distribution; easy to localise hot spots
The impulse response in a single position can be displayed and analysed in reflectogram and 3D reflection pathThe analysis in time and space is an efficient tool for optimising early reflections in an auditorium
Source directivity can be applied; the user can easily create new source directivity dataLoudspeaker data can be applied using the open CLF (Common Loudspeaker Format), which is supported by many loudspeaker manufacturers
Visualzation of reflections from selected surfaces, e.g. reflector panelsA 3D tool for design of reflectors