The air itself is the vibrator in the primary sense. The standing waves are significantly confined within the instrument itself. The air-stream passes through the player's vibrating lips, so gaining intermittent access to the air column which is to be made to vibrate. The body of the instrument is a tube with a wide conical bore, and holes to modify the pitch. Key bugles, serpents.
Labrosones with fingerholes
Labrosones with fingerholes and with keys, with (wider) conical bore
Labrosones with fingerholes, with (wider) conical bore
Hornbostel - Sachs