I watched this speech near every MLK day in the US while I was growing up, I remember sitting there not understanding it as I was in grammar school.

We watched it on a large TV set that they rolled in on a cart. Granted I was in a 99% white school at the time, but the school was not for the rich - however they bought the necessary footage (I assume now, no idea).

I distinctly remember Dr. King's voice, I will not forget it.