Moving-iron Instrument

The chromatic trumpet of Western tradition is a fairly recent invention, but primitive trumpets of one form or another have been in existence for millennia; some of the predecessors of the modern instrument are now known to date back to the Neolithic era. The earliest of these primordial trumpets were adapted from animal horns and sea shells, and were common throughout Europe, Africa, and India and, to a lesser extent, the Middle East. Primitive trumpets eventually found their way to most parts of the globe, though even today indigenous varieties are quite rare in the Americas, the Far East and South-East Asia. Some species of primitive trumpets can still be found in remote places, where they have remained largely untouched by the passage of time.
For the most part, these primitive instruments were “natural” trumpets: that is to say, they had none of those devices (fingerholes, keys, slides or valves) by which the pitch of an instrument might be altered. It is in fact quite exceptional to come across a chromatic trumpet – primitive or otherwise – which is not derived from the chromatic trumpet of Western tradition; the bãs of Madhya Pradesh in India, which has fingerholes bored into the side of its tube, is one such exception.
The simplest – and presumably the earliest – type of trumpet was made from the hollowed-out horn or shell of an animal, into the end of which a hole was bored for the mouth. This “trumpet” had neither a mouthpiece nor a bell, and was not so much a musical instrument as a megaphone into which one spoke, sang, or shouted. The intention was to distort the voice and produce a harsh, unnatural sound to ward off evil spirits or disconcert one’s enemies. Only later was the trumpet used to invoke friendly gods or to encourage one’s own warriors on the battlefield.
Typically only one or two different pitches could be produced on such an instrument, though sometimes a small fingerhole was bored in the tip to provide the player with an extra pitch. Most of these early trumpets were end-blown, like the modern trumpet; side-blown varieties, however, were not unknown, and can still be found in Africa and other parts of the globe