Some trombones have a trigger or “F” attachment. When you press the trombone trigger, the instrument lengthens 5 semitones (corresponds to the 6th position). The instrument produces a low F in 1st position instead of a Bb when you pull the trigger (or valve).
The F suffix on the trombone has two main purposes: It provides alternative slide positions for some notes. It offers a few lower notes. (It can also allow certain trills, but this is an advanced usage).
In general, a trombone’s F-trigger has three uses. First, it lowers the pitch of a tenor trombone a perfect fourth. This gives you access to an expanded spectrum that includes false tones and pedal tones. It also adds new options for positions like middle C in the 1st position instead of the 4th.
A bass trombone – only with F attachment. There are also single-valve bass trombones with a built-in F attachment (the Yamaha model in YBL-421G). The tubing length of a bass trombone with only an F embouchure is the same as that of a tenor bass, and both instruments can play the same range.
The trombone weighs approximately 1.3 to 2.8 kilos (3.0 to 6.1 lb). Your left arm weighs about 4 to 5 kg (9 to 11 lb) and you hold both up at the same time. All the time when you play. Of course, you can hold the trombone and left arm in a playing position, with your muscles constantly tensed.
The word “trombone” derives from the Italian tromba (trumpet) and -one (a suffix for “big”), so the name means “big trumpet”.
The trombone is in B flat major. Typically, bass trombones and many large bore tenor trombones have a trigger to bring the instrument into the key of F (the key down a perfect fourth).
RANGE: The trombone has a normal chromatic range from E2 below bass clef to B4 above middle C. Experienced performers can extend the upper range, often to F5 (or higher).
A typical professional F-bell tenor trombone model weighs about 4 pounds, 10 ounces. Bass trombones or instruments with heavy bells can weigh over 5 pounds.