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
Tenor horn whole-bore brass instrument, most players can play some pedal tones, the fundamentals (first partials) of (at least) the shorter tubing lengths. Tenor horn parts are written in the treble clef. The tenor horn is an E transposing instrument written a major sixth above concert pitch: the tenor horn notation for middle C represents the E below middle C in concert pitch (E in scientific pitch notation). The instrument known today as the tenor/alto horn was developed in the 1840s by the Belgian instrument maker Adolphe Sax who, among other instrument design activities, designed two similar families of valved brass instruments,