NOSE PRODUCING DEVICE AND REVERBERATION TIME MEASURING DEVICE USING THE SAME

PROBLEM TO BE SOLVED: To provide highly accurate measuring data hardly affected by a signal level in an adjacent band by imparting a first output mode and a second output mode for synthesizing/outputting output signals of an old numbered and an even numbered band pass filters to a noise output controlling means, respectively. SOLUTION: A noise producing device 1 comprises a noise generating source 2 for producing a noise and a noise output control part 3 for inputting the respective output signals of N band pass filters BPF1 -BPFN. The noise output control part 3 synchronizes/outputs N band noises outputted from N band pass filters BPF1 -BPFN so as to include the component for every two bands and has a first output mode and a second output mode. Since the first and second output modes are synthesized so as to include the component for every two bands, a signal component leaked from the adjacent frequency band is very small and hardly affects the result.