What does a symphony orchestra sound like while tuning before a concert?
Before a concert, a symphony orchestra tuning sounds like a bunch of gibberish and noise. There is no melody and no harmony, nothing worth listening to. Listeners can hardly wait until the musicians are ready and the curtain goes up so they can hear some music.
Les explains that unless somebody picks up an instrument and knows how to play it, bringing out the right tone at the right time within the score, you have a bunch of noise. He illustrates this with a symphony orchestra before the curtain: the musicians are tuning their instruments, and it is just gibberish and noise—no melody, no harmony, nothing worth listening to. You can hardly wait until they are all ready, the curtain goes up, and you hear some music. Paul applies the same principle to lifeless instruments: a pipe or harp must give a distinction in sound, the right note at the right place and timing, or no one will know what is piped or harped. You cannot make a melody or recognize the song otherwise. Les also notes the trumpet must give a certain sound for battle preparation.
And even things without life giving sound, whether pipe or harp, except they give a distinction in the sounds, how shall it be known what is piped or harped?