These are brass instruments. Trumpets, French Horn, Trombone, Tuba (in the middle). Tuba has the lowest pitch. Get used to the sound. Oh, and this is a brass quintet (5 brass instruments).
Brass instruments might use a mute to change the sound. Watch this to see how they work, and how the sound (or timbre) is different.
Click on the word to link to a definition and musical example.
intervals within the octave
broken chords (ex) The piano lower part is playing broken chords
sequence (ex) Here the main tune is repeated several times at the beginning beginning on different pitches, hence in sequence.
phrasing articulation pitch bend improvisation (ex) Here the trumpet improvises later in the piece.