A、The replacement of the harpsichord by the piano. B、The development of electronic musical instruments. C、The relative costs of

We are rapidly nearing the end of this course in the history of classical music. We have covered several centuries in a very short time. Much too short to do the music justice, of course, but then this is a survey course.[16]From now until the end of the term, we’ll be talking about and listening to electronic music. You probably already know it was in the 1950s that musical computers and synthesizers first appeared in universities. The first commercial synthesizers were sold about this time, too. The sophistication and complexity of these instruments has now increased to the point that they can produce almost any kind of sound.[17]Some alarmists believe these new instruments will bring an end to classical music or they already have. You know I don’t share this view, though I agree we are in the midst of a revolution in instrument design. This, however, is not the first such revolution in musical history and probably not the last one either.[18]Remember we’ve already studied a similar case in the early nineteenth century when the piano replaced the harpsichord and modern brass and wind instruments came into being.
    One of the most important reasons for the great popularity of electronic instruments is of course their relatively cheap price. Well, just look at it: Only about 400 dollars for an electronic keyboard compared to nearly 3000 dollars for a piano. Naturally, this has done a lot to increase sales of electronic instruments. But I don’t think even the most ardent supporters of electronic instruments expect them to completely replace acoustic instruments.
16. What is the speaker’s main topic?
17. What is the speaker’s opinion of the idea that electronic instruments will destroy classical music?
18. When does the speaker say another significant change in instrument design took place?