In a home theatre system, the front speakers deliver sound levels of 8.5 dB, 80 dB and 78 dB. The rear two speakers each deliver 75 dB. Assuming all measurement are made at the same listener's location. Calculate the total SPL deliver to the listener. Then, if one of the rear speakers is not functioning, determine the new SPL. After 2 months, some repair was done on the defected speaker, the measured of total SPL using sound level meter done by the listener is 90 dB, calculate the new sound level emits by this newly repair speaker.

In a home theatre system, the front speakers deliver sound levels of 8.5 dB, 80 dB and 78 dB. The rear two speakers each deliver 75 dB. Assuming all measurement are made at the same listener's location. Calculate the total SPL deliver to the listener. Then, if one of the rear speakers is not functioning, determine the new SPL. After 2 months, some repair was done on the defected speaker, the measured of total SPL using sound level meter done by the listener is 90 dB, calculate the new sound level emits by this newly repair speaker.