Mister, blow that horn.
10 seconds sound clip from the After the Thin Man (1936) movie soundboard.
You can hear this line at 00:29:43 in the DVD version of the movie.
Quote context
[...]
- Blow it high. Blow it down below. Got to try your hand at hidee-hi, you got to blow that horn.
- We're going to be a little bit daring. We're going to really start to get daring.
- Not now, baby. I got to make a change. I'll be right back.
- Waiter, bring Mr. Landis another drink.
- What's the idea? You better not leave that guy.
[...]