An orchestra may consist of as few as 50 members or as many as 100-plus. What percussion instrument can reproduce much of the scale of the orchestra by striking steel strings with felt-tipped hammers?

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How to find the answer: Searching for [percussion string instrument hammers] reveals that only dulcimers and pianos percussively strike strings with hammers. Reading about pianos and dulcimers reveals that only one, the piano, has the full range of an orchestra.