What Makes the Sound of Vuvuzelas so Annoying?

What better subject for the first post? Vuvuzelas! This unprecedented noise impact affected this year’s competition in the world’s most popular sport like no other year in recent memory, players and spectators alike.

If I may quote from the referenced article “A single vuvuzela played by a decent trumpeter is reminiscent of a hunting horn – but the sound is less pleasing when played by the average football fan, as the note is imperfect and fluctuates in frequency. It sounds more like an elephant trumpeting. This happens because the player does not keep the airflow and motion of the lips consistent.”

What large industrial power generator shares these traits- imperfect tone, fluctuates in frequency, airflow inconsistent; and above all, produces feelings of frustration, powerlessness, overwhelm and fatigue in people forced to listen to them?

The tenth person to write in and comment with the correct answer wins a copy of the critically acclaimed, international bestselling Wavepool, the Deep Relaxation Soundtrack!