 The Vienna horn is a special horn used primarily in Vienna, Austria.Instead of using rotary valves or piston valves, it uses the pumpenvalve (or Vienna valve), which is a double-piston operating inside the valve slides, and usually situated on the opposite side of the corpus from the player's left hand, and operated by a long pushrod.Unlike the modern horn, which has grown considerably larger internally (for a bigger, broader, and louder tone), and considerably heavier (with the addition of valves and tubing in the case of the double horn) the Vienna horn very closely mimics the size and weight of the natural horn, (although the valves do add some weight, they are lighter than rotary valves) even using crooks in the front of the horn, between the mouthpiece and the instrument.