The DK122A-L Geyer / Knopf Series offers the professional level player an instrument with a distinctive warm sound. The DK122 Horn features a .468-inch bore with a gold brass mouthpipe for a dark, warm sound plus a 12.2-inch detachable medium throat bell with excellent response and projection. The DK122A-L also features an in-line valve design based on Meister Fritz Knopf"s valve arrangement later adopted by Karl Geyer with the change valve placed in line after the third valve.