어서 떠들다

go somewhere and talk loudly

떠들다 is loud, unrestrained talking or general noise-making, and the commonest shape here is 가서/와서 떠들다 — going or coming somewhere to hold forth: 왜 여기 와서 떠들어?, 한국인들은 와서 떠들지 말고. Used that way it is a complaint about someone being noisy where they shouldn't be. But it can be neutral or fond too: 여기 가서 떠들더라고 is said warmly about a friend chatting away, and [추석을 앞두고 모여서 떠든 대화] simply means a get-together with lots of talk.

Register: casual; often critical