Name three percussion instruments which were added to the Romantic orchestra

Woodwind instruments like the contrabassoon, bass clarinet and piccolo made guest appearances in the orchestra to add some much needed colour, and the percussion section exploded in size with the addition of xylophones, drums, celestes, harps, bells, and triangles - when it comes to the Romantic period, the bigger, the better

Explanation:

i'm not sure i completely understand your question, but i will do my best.

i think the answer you are looking for is sequence. (see below)

a repeated melodic fragment would be best defined as repetition, while repeated chords (different or the same) could be a chord progression. however, you then mentioned the chord and melodic fragment beginning on higher or lower pitches, in that case, the answer could be best defined as a sequence. the definition of a sequence is as follows: "the restatement of a motif or longer melodic (or harmonic) passage at a higher or lower pitch in the same voice."

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