18"

B A 70 dB

C A 72 dB

A A 69 dB

C C 74 dB

C B 70 dB

B A 71 dB

B B 71 dB

C A 70 dB

B A 72 dB

A C 72 dB

A B 68 dB

C B 69 dB

C A 71 dB

B B 71 dB

D A 72 dB

C A 71 dB

B B 73 dB

D B 70 dB

B C 71 dB

C B 70 dB

B B 72 dB

A A 69 dB

D C 73 dB

C C 70 dB