The buzzing gives Tachibana pause. And something to focus on. His has his Buckle this time, And he was much stronger than he was after Karasuma had fished him out of the ocean...

Better get the hell out of the way, Jack, because that sound you're hearing in addition to that buzzing is the standby of Tachibana's Belt activating, and he's not going to give you much more of a warning than that and his yelled "Henshin!" before that projection is rushing out, with him following.