Why are there so many string instruments in a classical orchestra compared to other instruments?
[i]Listen to Bach’s 2nd Brandenburg concerto. There are four solo instruments, a high pitched trumpet, an oboe, a flute, and a violin. I admit that this composer was ultra skilled at part writing, but I guarantee you will not find the violin difficult to hear. The first (sometimes the only) reason given by apologists for the orchestra, vis., that the stringed instruments are ‘too soft’ to play on their own, is hardly valid, then? [ii] Physics tells us emphatically that low pitched sound in nature is brighter (more equipped with harmonics) than high pitched sound. Good polyphony in music assumes equal audibility, and, for this, the bass is to be ‘brighter’ than the treble, and the treble, in general, to be ‘duller’ than the parts under it. (n.b. It is NOT sufficient for the bass to be ‘Louder’!) [iii] The string section in the symphony orchestra is topped by violins, notably brighter in tone than those of the other string family. Further, there are many more Violins than there are Viola
