Question

A)If one clarinet causes a 77dB (sound level), then two clarinets cause how large a sound level in decibels?

B) 5 clarinets?

C) 7 clarinets?

Answers in dB

Answer 1

The sound intensity level in decibel (dB) is defined in terms of the sound intensity as
   
And so, If there are N identical sound sources each with intensity I, then, the total sound intensity is

the accumulated sound intensity level of this N source is given by
   
  
where,
    is the sound intensity level ( in dB) of the single sound source.

A)
Given the sound level of a single clarinet ,
in the case, when there are two clarinets, N = 2. So, the accumulated sound level of the two sources is


B)

in the case, when there are two clarinets, N = 5. So, the accumulated sound level of the two sources is


C)

  in the case, when there are two clarinets, N = 7. So, the accumulated sound level of the two sources is