Reducing a 100 watt audio system's SPL output by 3dB results in how much power?

To understand how reducing a 100 watt audio system's SPL (Sound Pressure Level) output by 3 dB affects power, it’s essential to grasp the relationship between sound level (in dB) and power output in audio systems.

The decibel (dB) scale is logarithmic, which means that a change of 3 dB represents a halving of the power output. Specifically, when SPL is reduced by 3 dB, the power level needed to achieve that SPL is reduced to half of the original power.

In this case, starting with a 100 watt system, reducing the output by 3 dB translates to halving the power:

100 watts ÷ 2 = 50 watts.

Thus, when the SPL output decreases by 3 dB, the corresponding power output becomes 50 watts. This is why the correct answer is 50 watts.