There are many papers written about the practice strategies of top musicians. Against linear thinking and the assumptions of the masses, high level musicians do not practice more hours than their less accomplished colleagues. At least not at the later stages! Practice strategies should certainly not be the same for beginners and advanced musicians, and for singers it is even more individual than other musicians. Different singers come into serious study with different assets, and classical singers have so many different skill-sets that they must master that it would be ludicrous to suggest a single practice regimen for all singers.
Of all my musical skills, keyboard skills lagged behind for a long-time because I did not have the luxury of piano lessons when I was young. Now I routinely accompany my students (usually playing reductions of what is on the page) to sometimes satisfying results. I do well with composers who were not virtuoso pianists and who wrote more orchestrally. I think my study of orchestral conducting may have a bearing on this particular skill. I am no pianist! Some of my students will attest to the obvious fact. But there are many accompaniments that I can fake very well at sight. Today I was looking at a Beethoven accompaniment (typically pianistic, which does not accommodate my week piano skills) and began to see that the patterns were not as difficult as I used to think. Some rapid scale passages that I would not consider at all doable before suddenly became possible if I dedicate time to practice. But how would I practice a difficult Beethoven piano reduction?
The specifics of the how I leave to my able pianist-colleagues. What I do know is that I would not approach this piece the way I might have 10 years ago, which would have been many hours of repetition. Now I know my way around the keyboard enough, from hundreds of hours of sight-reading accompaniments, to realize that my time would best be spent slowly learning the patterns in each hand and putting them together.
For singing technique, practice regimens also vary depending on skill level and knowledge of self. There are three levels of skill in vocal technique: 1) Gross motor-skills and strength-building 2) Fine-motor skills and strength-building and 3) Coordination of technical elements.
1) Gross Motor Skills require repetition. It is like going to the gym to development fitness, strength and muscle tone. Singers need this as well. Some singers, because of excellent speaking habits or vigorous singing traditions, come to early training already having developed muscle tone and strength. These singers are called gifted, talented, etc. With such singers, it is not necessary to spend a lot of time of fitness, but it is important to teach them exercises that will help them become aware of their fitness and to maintain it.
Gross motor skills include basic balance between heavy and light mechanism and moderately efficient glottal closure. Too often singers are asked to accomplish perfect efficiency in phonation before the muscles have been developed to accomplish it. The voice is not a one dimensional instrument whereby one could isolate the Inter-arytenoids to achieve ideal fold closure. On a note that is overly defined by the heavy mechanism, ideal closure will not be possible unless it is forced, nor can true flow-phonation be possible in a voice that is too dominated by the light mechanism. Issues of vocal weight and glottal efficiency depend on each other and the student must know at what level of proficiency s/he is in order to have expectations commensurate with their skill level.
2) Fine Motor Skills include refinements in vocal mass and fold length to achieve ideal balance between heavy and light mechanism. The specifics will vary from one pitch to the next. At this level, the singer should have conscious control of intrinsic musculature by sensory feedback. The singer must also work on glottal efficiency, keeping in mind that actual fold closure, balance of vocal weight as well as control of volume (sub-glottal pressure) all depend on a dynamic interaction. The mental focus required for this level of exercise should not be sustained for long periods of time. I see singers getting frustrated when they spend too much time on balancing these elements. At this level, shorter and very goal-oriented practice is crucial. The singer must be able to understand sensations related to fold mass (what some might call anchoring, grounding, etc), fold lengthening and closure (what some might call stretching and focusing) as well as conscious volume control at the onset of sound. Combining these skills is initially a frustrating process for many singers. For that reason, long practices that become more and more mindless do not help. Just as the high level pianist or violinist who may work on a specific étude to develop a specific skill, singers must also have pieces designed for specific skill sets. A former baritone turned tenor worked on Mozart’s “Dalla sua pace” initially to develop the basic strength required to handle the tenor tessitura. Many months later after not singing the piece for a long time he picked it up again for a different purpose, namely glottal efficiency and dynamic control.
3) Final Coordination includes not only the refinement skills in (2) but also issues of articulation of vowels and consonants (which has repercussions on legato and phonation efficiency), resonance tracking/vowel modification (which would have repercussions of fioratura, trilling and acoustic passaggi) and musical details (i.e. harmonic structure of a musical line, diction vs. technical necessities of vowel alteration, dramatic interpretation vs. technical limitations, etc).
The higher the level of proficiency, the more there is to consider. I watch singers who were emotionally very scattered become very focused with respect to their vocal studies as well as their lives. When singers begin to understand the elements of singing that they can control, particularly when they are trained enough to experience the instrument responding to their will, they will begin to practice differently.
It is possible for a beginner to be able to perform very advanced skills while a much more proficient and experienced singer may have difficulties with the very same skills. Very advanced singers may have minor weaknesses in very specific parts of their voices because of training history. In such cases they may have two modes of practicing: A) developing strength and fitness in the weak areas and B) working on refinement and coordination in otherwise well structured regions.
In short no two singers have exactly the same needs. Effective practice particularly at the higher levels of proficiency need to be deliberate, conscious and specific, whereas regimens for beginners, particularly those who need fitness training, can be more general and based on sheer repetition.