I get this question often from those who are past college-age and the answer is that it depends on your goals. Private lessons and music schools both offer a musical education, but with a different emphasis.
Private voice lessons allow you to receive customized, technical help with your unique voice. This is critical for you to progress technically and have your voice develop in a healthy way. By studying privately, you have the ability to choose the teacher that is just right for you and study as much as you want. Practicing regularly at home reinforce the concepts you learn during your lessons. Private voice teachers usually also offer help with languages, musical interpretation, choosing appropriate repertoire, audition preparation, etc.
In order to be a singer of any genre, all you really need is to be able to sing well. Private voice lessons provide the training needed to improve your voice and help you reach your goals. However, they do not provide the additional knowledge and deeper understanding of music needed to become a wonderful musician. Further instruction from vocal coaches (pianists who know the classical vocal repertoire, languages and musical style) can help develop your musicianship and understanding. Reading up on music history, listening to singers and learning the repertoire, and taking classes in performance, languages, music history or theory, and repertoire here and there can help you become a more well-rounded musician without requiring you to enroll in a formal program. This approach can work well if you are motivated to become as educated as possible and can structure your time well.
Music schools, either conservatories or departments within colleges and universities, offer music degree programs for students. Most music schools have an emphasis on classical music, though there are some schools that specialize in pop music and some that also have small vocal jazz programs. As a performance major, these schools have a curriculum that requires you to study music theory, music history, ear training, repertoire, and more, as well as participate in ensembles, perform at least one solo recital and study privately with a voice teacher on faculty. At colleges and universities, there are also non-music classes required for graduation.
Because you can only study with a teacher on faculty, your options are limited and even more limited by the fact that the best teachers often have full studios. That means you can easily get stuck with a mediocre teacher who can’t help you improve very much and from whom you have to get a grade every semester. Only by working with various teachers and securing a spot in the studio of your desired teacher in advance can you ensure that you will have a teacher who will be able to help you improve vocally. In fact, many singers choose their schools based mainly on the voice teacher. You will normally receive 15 hour-long lessons per semester, adding up to 30 per school year. Depending on teacher availability, you might have difficulty taking additional lessons, leaving you without technical instruction and support the rest of the time.
Music schools do provide a well-rounded musical education and being around a group of faculty and fellow musicians, exchanging ideas, and hearing master classes and performances regularly can be very stimulating and help you grow as a musician. However, earning a degree takes four years and can take even longer if you plan to attend part-time. There is also a financial burden to be considered.
In summary, private voice lessons and music school both provide important training for singers. It simply depends on what your emphasis and needs are.
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