Inspired by a photograph of some seriously large Bavarian/Swiss/Austrian horns - the ones with the long slender tube and the big bowl at the end.
When the the first Dwarfs emigrated to Rimwards Howondaland, enticed by the rich gold deposits to be found underneath that country and a promise that if they ran the mining operations for the humans they could keep 20%, a really big problem was that of hermit elephants nesting in the krumpelhorns. Dwarfs, being a pragmatic people, then started breeding hermit elephants to take the place of pit ponies, pointing out to the notoriously shy creatures that they could dwell in peace and safety and above all remain inconspicuous in the dark. The mutual trust between Dwarf and Hermit Elephant as mutually dependent species is a wonder to behold and indeed Dwarfs now compete in their own breeding fancy with show elephants, much in the manner of Lady Sybil Ramkin and swamp dragons. A Hermit Elephant in a Howondalandian dwarf mine can usually be seen wearing a shell which is a heavily modified and above all muted krumpelhorn; it was held after early failed experiments that a happy elephant trumpeting down a krumpelhorn is not what you need in a mine working a mile underground. However, on the surface where the beasts are turned out to pasture at the end of a working shift should they wish to, the mating call of a Hermit Elephant now carries for miles.