Definition and background:
A small valved Brass instrument in the key of E -flat related to various members of the brass family. Rarely used in modern ensembles as it was replaced by other instruments. The written range is the same as the cornet but sounds a major sixth lower ( F- sharp to c 3). The Alto Horn resembles a small upright tuba and can be found in English brass bands.
American term for althorn
For more information on the music term "Alto horn" check out these other resources:
Wikipedia - Glossary of Musical Terminology
Virginia Tech Multimedia Music Dictionary
ORB -- Medieval Music Glossary