From Academic Kids
Known in the US as alto horn, in Germany as althorn, and in the UK as tenor horn, this brass instrument pitched in Eb has a conical bore (gradually widening), and normally uses a deep, cornet-like mouthpiece. It is most commonly used in marching bands, brass bands and similar ensembles, whereas the French horn tends to take the corresponding parts in symphonic groupings and classical brass ensembles. In the US and Germany the name tenor horn is identical with baritone horn.
The tenor horn has a conical bore like the orchestral (french) horn and uses deep funnel or cup shaped mouthpieces depending on the model. It is used in British Brass bands and is very rarely included in the orchestra where its place is taken by the orchestral horn. The conical bore and deep mouthpiece produces a mellow, rounded tone which is most often used as a middle voice, supporting the melodies by the trumpets, cornets or flugelhorns, and fills in the gap above the lower tenor and bass intruments (the trombone, baritone horn, euphonium and Tuba). Solos for the Tenor Horn are very occasional, and are usually taken by the solo horns. Most Tenor Horns are pitched in Eb and are transposing instruments. Their typical range is from the A below middle C to the Eb above the C above middle C.The standard bell-up horn comes in two basic shapes. One with the beginning of the bell looping over the top of the valves and the other looping below the valves.
Tenor horns are very free-blowing instruments and intermediate players should be able to reach the high register (from the F above middle C onwards). Its beautiful mellow tone is most evident in this register and the notes at the bottom of its range sound less mellow.
To produce a tone a player buzzes his lips by tightening them and gently forcing air out. The mouthpiece should be pressed gently against the lips and the rim of the mouthpiece is used to sustain the correct lip position.
To reach higher notes, the lips are tightened further and the player should blow the air at a faster speed. Without using the valves, the player can play Eb, Bb, Eb, G, Bb, C# and double high Eb (untransposed) in ascending order. These notes are part of the horn's harmonic series.
The three valves lower the notes by 2 semitones, 1 semitone and 3 semitones respectively. By using a certain combination of these valves, all the notes in the chromatic series can be played; for example:
To play a D#(as on the Tenor Horn)
Since the valves only lower the note, the closest harmonic note above D# is used, in this case a G (Bb on the piano). From G to D# is 2 tones or 4 semitones, the pitch to be lowered by. Therefore the valve fingering is 2-3 (which means the 2nd and 3rd valves are depressed) because 3 semitones (the 3rd valve) + 1 semitone (the 2nd valve) = 4 semitones (the pitch difference between D# and G).
It was invented as a tenor or alto voice in the saxhorn family invented in the mid-1800s by Adolphe Sax, a Belgian who is best remembered for the saxophone. It has been made in various forms: most common is a sort of mini-tuba shape, with the bell pointing upward, which may help the voice blend before reaching the audience; the solo horn looks like (and indeed effectively is) an enlarged flugelhorn, with the bell pointing forward, projecting more toward the audience; another variant has the bell facing backward (for military marching bands that preceded the soldiers, thus helping them hear better and keep better time in marching). Of these types only the standard upright instrument is seen in UK brass bands and remains the most common configuration seen.