PC YUEN
March 30th, 2009, 10:44 AM
We just bought Acoustic Tools V4 and needed to apply in a concert hall acoustic setting. Questions as below:
1.For the FFT size problem, if we don’t have idea of the expected decay time, how can we set/select the FFT size or should we set this FFT size as large as possible?
2. In our target Concert Hall, when we measure the RT60 different results are recorded according to different FFT size? We tried to set the FFT size from 128k thru 320k, the value of RT60 were recorded from 0.7 to 2.3. We cannot justify the final RT60 values, which is true/ appropriate?
3. The Ln of the signal we captured always in a high level, some time it will higher than Lr2 10dB. Is it normal? Or some requirement and setting we missed?
4. In the Intelligibility Graph our Clarity Factor reading always sticks in the left side (BED section), what can we do to solve this problem? Or any wrong setup will cause this problem happen?
It is urgent.
Many thanks.
1.For the FFT size problem, if we don’t have idea of the expected decay time, how can we set/select the FFT size or should we set this FFT size as large as possible?
2. In our target Concert Hall, when we measure the RT60 different results are recorded according to different FFT size? We tried to set the FFT size from 128k thru 320k, the value of RT60 were recorded from 0.7 to 2.3. We cannot justify the final RT60 values, which is true/ appropriate?
3. The Ln of the signal we captured always in a high level, some time it will higher than Lr2 10dB. Is it normal? Or some requirement and setting we missed?
4. In the Intelligibility Graph our Clarity Factor reading always sticks in the left side (BED section), what can we do to solve this problem? Or any wrong setup will cause this problem happen?
It is urgent.
Many thanks.