THE TROMBONE TRIGGER MAKES IT LONGER

Single trombone trigger

Some trombones have a trigger or “F” attachment. When you press the trombone trigger, it makes the instrument longer by 5 semitones (equivalent to 6^th position).  The instrument will produce a low F in the 1^st position instead of a Bb when you press the trigger (or valve).  Therefore the trigger is often referred to as an “F attachment”. 

The trigger provides further options when playing notes in 6^th or 7^th position.  The trigger make the trombone much longer when used in combination with the slide by adding another 6 positions in length to the 7 positions on the slide.  The player uses the trigger to continue playing all the way down to a low C (just above pedal Bb) from a low E in 7^th position.  With only 1 trigger, the instrument still can’t be made long enough to reach a low B natural.

Double trombone trigger

The 2^nd trombone trigger on some bass trombones opens several more semitones of tubing.  By combining two triggers with the slide, the trombone can be made much longer than usual; allowing it to play much lower notes, including the low B natural.

Length of positions

When you press a trombone trigger, you are lengthening the whole instrument. The length of the instrument determines how long each position should be to reach the next semi-tone. When you press a trigger, you make the slide positions become so long, that the slide is only long enough to cater for 6 positions, instead of the usual 7 positions. 

To find the new longer positions when the trigger is pressed, do the following;

• Play F in 1^st position, press the trigger and tune the trigger to sound the same.
• Play E in 2^nd position, press the trigger and find the same note using a long 2^nd position. Use the trigger and this long 2^nd position to play the E an octave lower.
• Play Eb in 3^rd, then find the longer 3^rd by pressing the trigger, and so on until you get to C.

Find the (even longer) positions using a double trigger using the same method.