On the practical side, the nature of the problem is by no means so simple. In actual instruction in singing, the subject of vocal management cannot readily be dissociated from the wide range of other topics comprised in the singer's education. In much that pertains to the art of music, the singer's training must include the same subjects that form the training of every musician. In addition to this general musical training, about the same for all students of music, each student must acquire technical command of the chosen instrument. This is necessarily acquired by practice on the instrument, whether it be piano, violin, oboe, or whatever else. In the same way, vocal technique is acquired by practice in actual singing. Practice makes perfect, with the voice as with everything else. But the voice is not invariably subject to the law that practice makes perfect. In this important respect the singer's education presents a problem not encountered by the student of any instrument. Given the necessary talents, industry, and opportunities for study, the student of the violin may count with certainty on acquiring the mastery of this instrument. But for the vocal student this is not necessarily true. There are many cases in which practice in singing does not bring about technical perfection. The mere singing of technical exercises is not enough; it is of vital importance that the exercises be sung in some particular manner. There is one certain way in which the voice must be handled during the practice of singing. If the vocal organs are exercised in this particular manner, the voice will improve steadily as the result of practice. This progress will continue until perfect technical command of the voice is acquired. But if the vocal student fails to hit upon this particular way of handling the voice in practice the voice will improve little, or not at all. In such a case perfect vocal technique will never be acquired, no matter how many years the practice may continue. What is this peculiar way in which the voice must be handled during the practice of singing? This is the practical problem of tone-production, as it confronts the student of singing.