Architectural acoustics can be about achieving good speech intelligibility in a theater, restaurant or railway station, enhancing the quality of music in a concert hall or recording studio, or suppressing noise to make offices and homes more productive and pleasant places to work and live in.
Problems due to poor or no acoustical treatment
Focusing of Sound - Occurs with use of parabolic surfaces either behind performers or at rear of auditorium.
Echoes - Highly reflective flat or parabolic wall shapes, Flutter echoes from parallel walls, Standing waves between parallel walls.
Resonances - Parallel walls, Rectangular practice rooms, singing in the shower
External noise- Box within a box construction, Practice rooms and concert halls in adjacent areas.
Characteristics for good acoustical treatment
Liveliness - Measure of reverberation time
Intimacy - Room said to be “intimate” when the first reverberation arrives within 20 ms of the direct sound.
Fullness vs. Clarity - Refers to the amount of reflected sound relative to the amount of direct sound.
Blend and Ensemble - Ability to hear the entire performing group on the stage (ensemble) and in the audience (blend).
Common reverberation times in various spaces in seconds