Why do BBCOR Bats...?

I've been watching the College World Series in the past few weeks, and I know that they had to switch over to BBCOR, so when I heard their hits, it didn't sound like the normal ping, but kind of like shattering glass. I don't know if thats the echo of the stadium doing that or what. If anyone could tell me if they sound like this, I appreciate it. Kinda weird. Thank you.