Green’s Dictionary of Slang

pipes n.1

1. [mid-16C+] the voice.

2. [18C+] the lungs, esp. of a singer.

3. [early 19C+] (also pipe) the throat.

4. [1990s+] (US campus) the upper arms.

5. [2000s] the vocal chords.

6. see pipe n.1 (1d)

In phrases

clear one’s pipes (v.)

1. [mid-17C; mid-19C] to take a drink in order (lit. or fig.) to clear the throat.

2. to clear one’s throat, esp. preparatory to singing.

3. [early 18C; 1980s] in fig. use, to lose one’s emotions, to ‘let off steam’.

knock one’s pipes out (v.)

[1980s] to work oneself to exhaustion.

open one’s pipes (v.)

1. [18C+] to sing.

2. to clear one’s throat.

put up one’s pipes (v.) (also pack up one’s pipes, poke up ...)

[mid-16C–mid-18C] to cease from an action; to stop talking.

set up one’s pipes (v.)

1. [17C] to yell, to scream.

2. to complain; to make a fuss.