“What’s the difference between an opera and a musical? Theories abound. Some say opera is through-sung while musicals include spoken dialogue (although there are many operas with spoken dialogue; think Carmen). Some say opera is unamplified, while musicals are mic’d (except that there are many operas written for amplification, and many musicals that weren’t). But ask Stephen Sondheim … and you’ll hear that it has to do largely, simply, with the expectations of the audience. Sondheim should know.”