Answer
Because when the speakers are wired with opposite polarities, the sound waves from the speakers interfere with each other in a way that cancels out certain frequencies.
Work Step by Step
- When stereo speakers are wired correctly, the sound waves produced by each speaker are in phase with each other, meaning that the peaks and troughs of the waves line up.
- When the speakers are wired with opposite polarities, the sound waves produced by each speaker are out of phase with each other, meaning that the peaks of one wave line up with the troughs of the other.
- When sound waves are out of phase, they can interfere with each other in a way that cancels out certain frequencies. This is known as "phase cancellation".
- When phase cancellation occurs, the frequencies that are most affected are the lower frequencies, or bass. This is because lower frequencies have longer wavelengths, which means that they are more likely to be affected by phase cancellation.
- Higher frequencies, or treble, have shorter wavelengths, which means that they are less likely to be affected by phase cancellation. Therefore, the bass (low frequencies) are weakened more than the treble (high frequencies) when the stereo speakers are wired with opposite polarities.
