1. Warm, BR
For the reverberation time of 2.2s concert hall, BR optimum value is between 1.1~1.25 and concert hall reverb time 1.8s or shorter, optimal values between 1.1~1.20 BR, between the reverberation time of 1.8~2.2s Concert Hall, its optimal value can be determined by the insertion of the BR.
2, the intensity factor G (subjective)
Receiving point for sound energy density or sound field G, suitable for the sound level of the audience 77~80 (a), Gmid-500Hz~1000Hz, on average Gmid best value for 4~5.5dB in the design of the concert hall. (Detailed reference of the architectural acoustics and audio engineering)
Acoustics design measures: shape; there should be more of the early reflections. Bounded by 80ms, the width between the two walls value at the source for 17~18m.
3, definition/clarity C80 (objective)
The sound parameters: effective sound at the receiving point and void ratio of acoustic energy (C80). Ratings higher Hall, C80 values smaller, concert hall, optimization of Stope C80 value should be between -1~4.
4, relative T1 (subjective)
The initial time delay gap of early reflections (T1), optimum design value is 20s, more than 35ms is negative.
Acoustics design measures: shape; the time difference between the direct sound and reflection sound (is about 20ms), the distance between the reflector and receiver is about 7m.
5, a sense of space and surround
More or early lateral reflections (LEV)
Acoustics design measures: shape; early reflections of time-space-energy should reasonably distribution.
- A. Noise volume: noise allow standard NR ≤ 20 a;
- B. Sound distribution: no disturbance of echo;
- C. Classical period, hundred seats of concert halls, its T60 is about 1.0~1.3s; the romantic period, 500~800 seats of concert Hall, its T60 is about 1.5~1.7s.