The sound of a pneumatic tube system
Soundrecording of a pneumatic tube divider changing position
An electric motor turns the pipe in the divider to another output. This way a carrier can exchange tubes.
The sound of a carrier exchanging tubes through a divider
At first you hear the divider turn to the right tube, the blower starts sucking the carrier towards the divider.
The carrier passes the divider and the blower stops for a moment.
The divider turns to another tube and the blower blows the carrier into that pipe of the transfer zone.
In the end the pipe in the divider turns back to its original position.
The sound of a carrier arriving at a station, and another one leaving
Soundrecording in the engine room
Just a recording of the sound in the pneumatice tube engine room. You hear blowers blowing and sucking, relays clicking, dividers turning and carriers passing by.