He was perched on top the coal and straining his ears for the sound of someone blowing on a trumpet.
9 seconds sound clip from the Destination Freedom - The Trumpet Talks (The early life of Louis Armstrong) classic radio play.
You can hear this line at 00:04:56 in the radio play.
Quote context
[...]
- And the kid guided it towards the back of Diamond Stone's Cafe.
- He stopped his wagon at the door.
- He was perched on top the coal and straining his ears for the sound of someone blowing on a trumpet.
- And inside, the drummer gripped the trumpeter's arm and held him back.
- Just make like we haven't started practicing yet.
- Too bad 'nothin.' Let him grow into long pants first before he grabs at a trumpet.
[...]