20"

D B 72 dB

C C 71 dB

C A 70 dB

B A 70 dB

D B 73 dB

C A 72 dB

B A 70 dB

B B 70 dB

B A 71 dB

C C 71 dB

C B 72 dB

C A 73 dB

A B 69 dB

C B 72 dB

A C 69 dB

A C 69 dB

B A 70 dB

B C 69 dB

C C 71 dB

C B 71 dB

A A 70 dB

D A 71 dB

D A 73 dB