2. The Space of the Listener Yew Tze Ee

3. Reverberation  Persistance of sound in a particular space after the original sound is produced  Caused by echoes (reflections) in an enclosed space

4. Reverberation Time and Speech  Dry speech, without reverberation  Speech with a 0.8s reverberation time  Speech with a 2.0s reverberation time  Speech with a 5.0s reverberation time

5. Reverberation Time and Music  Dry music, without reverberation  Music with a 0.6s reverberation time  Music with a 1.5s reverberation time  Music with a 2.5s reverberation time

6. Ideal Reverberation Time  Reverberation time (RT60):  Amount of time required for the sound field to decay 60bB of its original power.  For both speech and music: RT60 < 1s (from Knudsen)

7. Concert Hall Acoustics  Sound waves from a stage are deflected by sound panels and distributed throughout an auditorium

8. Concert Hall Acoustics Direct sound vs Lateral reflection  Lateral reflection:  Difference in intensity in left/right ear and different arrival time  Brain senses being enveloped by the music  Characteristics of a good room acoustics  Direct sound:  Same signal in both ears  Feeling of ‘missing something’  E.g. Listening through headphones

9. Types of Concert Halls Shoe Box Shape  Shoe box shaped halls are good for concert halls because of beneficial lateral reflections  Shoe box concert halls are long, tall and narrow Royal Festival Hall Southbank Center, UK

10. Types of Concert Halls Fan Shaped  Influenced by amphitheatres, theatre and early cinema  Lack of lateral reflections Liverpool Philharmonic Hall Liverpool, UK

11. Types of Concert Halls Vineyard Terrace  Audience are subdivided  More beneficial reflections from dividing walls Waterfront Hall Belfast, Northern Ireland

12. References  http://www.mcsquared.com/problems.htm http://www.mcsquared.com/problems.htm  http://www.acoustics.salford.ac.uk/acoustics_ info/concert_hall_acoustics/?content=shape http://www.acoustics.salford.ac.uk/acoustics_ info/concert_hall_acoustics/?content=shape  http://images.yourdictionary.com/acoustics http://images.yourdictionary.com/acoustics

13. THE END Thank You