Ah, now you're describing the EBS test that replaced the first one I described.
The new one featured a bunch of quick clips from songs, starting with things like (if I remember correctly) Randy Newman "let's drop the big one," Skeeter Davis "it's the end of the world," The Shangri-Las "lookout-lookout-lookout-lookout!!" and then a big explosion. As it fades, the announcer does the official EBS spiel. Then the tone, then the announcer close, and finally, "let us live in peace."