Appointment of a cantor

I once read a story about Rabbi Chaim Brisker, who in a certain community wanted to appoint a cantor, and there were two people, one who had an Arab voice and no other requirements, and one who had all the requirements except an Arab voice, and Rabbi Chaim said to appoint someone whose voice was Arab because that is the desire of a cantor, compared to the other things that are only requirements for a cantor.
And now to my question, I don't understand where Rabbi Chaim got the idea that a cantor's voice is an Arab voice. After all, we are not talking about a singer, but rather a prayer leader who is supposed to pray for the congregation and bring them out of their obligation. What does his Arab voice have to do with this?