The Broca-Sulzer effect is when we hear sounds better with our right ear than our left ear. This happens because the way our brains process sound is different on each side.
Imagine you are in a big room with a toy that makes a sound. When you listen with your right ear, the sound goes directly to the left side of your brain, which is really good at processing sounds that have to do with language (like words and sentences). When you listen with your left ear, the sound goes to the right side of your brain, which is better at processing sounds that have to do with music and tone (like different pitches and rhythms).
When we hear speech, it's really important for us to understand the words so we can communicate well with others. That's why our right ear is better at processing speech sounds, because it sends the information straight to the part of our brain that's really good at understanding language.
So, the Broca-Sulzer effect happens because our brains are set up differently on each side. Our right ear is better at understanding speech, while our left ear is better at understanding tone and music.