We live one block from a mosque, so we hear the call to prayer every day, five times a day, but on Fridays, we hear the sermon that is piped through the speakers for the whole neighborhood to hear.
I guess it's a chance for everyone to hear.
Each neighborhood here has a mosque. In fact, you can tell a taxi driver where you live by naming the mosque closest to you.
So basically, they are everywhere.
That means, on Fridays, I can hear multiple sermons at once, and this is what it sounds like.