Brass instrument can be very useful for a 1st or 3rd horn player, who uses the F side less. Another approach was the addition of two sets of slides for different parts of the range. Some euphoniums and tubas were built like this, but today, this approach has become highly exotic for all instruments except horns, where it is the norm, usually in a double, sometimes even triple configuration. Some valved brass instruments provide triggers or throws that manually lengthen (or, less commonly, shorten) the main tuning slide, a valve slide, or the main tubing. These mechanisms alter the pitch of notes
Brass instrument piston valve instruments were developed just after the start of the 19th century. The "Stölzel valve" (invented by Heinrich Stölzel in 1814) was an early variety. In the mid 19th century the "Vienna valve" was an improved design. However many professional musicians preferred rotary valves for quicker, more reliable action, until better designs of piston valves were mass manufactured towards the end of the 19th century. Since the early decades of the 20th century, piston valves have been the most common on brass instruments except for the orchestral horn and the tuba. See also the article Brass Instrument Valves. Because