This is just my opinion as a classical singer who also sings musical theater (and the Lead part in a barbershop chorus).

 

1.  Some of the "problems" with Musical Theater singing for the classical voice are really only problems if the singer isn't easily able to adapt from one style to the next.  Many people think that all current musical theater shows are sung mainly in high Belt voice - while it's true there are a number of shows that are sung predominantly in a belt voice, there are plenty of shows out there that feature more "legit" singing (mixed voice or head dominant).  The switching back and forth between singing with vibrato at all times (my classical voice) versus singing straight tone until the ends of phrases (my musical theater style) is the bigger challenge.  My voice teacher often has to remind me to sing more vibrantly.  The other challenge for me is I often want to sing lower pitches in my classical rep in pure chest voice, where my voice teacher prefers I sing in more of a mix.

 

2.  Belting done properly does not hurt the voice but can result in the singer having weaker cricho-tyroid muscles as a result of always singing thyro-arytenoid dominant.  It's like any other set of muscles that work in conjunction with another -- a swimmer who always uses the arms to stroke without kicking the legs is going to have a hard time making it across the pool holding a kickboard.  A singer who belts correctly and also sings in head voice dominant production won't experience the same weak sound up high in head voice as one who never uses head voice production. 

 

Now belting done improperly is another story.  If done improperly, there is risk of vocal damage of varying degrees from muscle exhaustion to vocal nodes to polyps. 

 

3.  As for benefits - that depends on what you mean.  If you are a working classical singer, having musical theater credits on your resume is not likely to help in purely classical auditions (and I've heard stories of it actually hurting).  If you are looking to be a working singer, period - then having a wide variety of musical styles that you can perform well can open you up to more markets and more jobs.  It's very difficult to excel in both arenas though - if one wants to be a "star" in either genre it's better to focus on one or the other, but if you are more of an ensemble or bit part singer, then being accomplished in both arenas can help you find more steady work.

 

Hope this helps.  Again, it's just my opinion based on my experiences.  I'm sure others may have other opinions.

 

Jennifer Newman

Masters of Music in Voice Performance & Pedagogy, pedagogy emphasis, Westminster Choir College - Class of 2013

Bachelors of Music in Music Education, James Madison University - Class of 1992

Just want to chime in here even though Jennifer gave an excellent response.

 

Speaking from someone who also is a classically trained vocalist, (tenor) who also sings musical theater, here's kind of the essence of things:

 

Good technique applies to all styles.

 

BUT, for the young singer (now I'm talking like someone through their 20's into early 30's), and especially tenors and mezzo's, sticking to one style has a wealth of benefits for being able to apply your technique consistently while your voice settles.  Basses and many soprano's have the luxury of having a settled voice sooner and therefore can usually switch between styles relativley young without much detriment.  But the tenor or mezzo who chooses to do likewise can often face challenges simply because their voice keeps changing physiologically speaking.  When the physical side of things keeps changing, you have to learn how to keep adjust your technique until your voice settles.  That doesn't mean you can't have a wonderful career early one, and yes some people "get it" sooner than others.  But as a general rule of thumb, especially for singers in their undergrad, sticking with one style (and the general consensus is a classical style) will be much more beneficial than switching between different styles.  

 

That's not to say there isn't a fair amount of misunderstanding out there.  Some singers even say they sing with a "jazz technique" or a "musical theater technique".  Young singers, or those who just don't understand the voice, often confuse technique with style.  The voice, in this case, is much like any other instrument, there is a right way to do things that will prepare you for a life of singing well with the knowledge of how best to use your instrument.  A piano, for example, can simply be played, can be learned by many people and can be played in a variety of styles, but there are few true pianist who can bring out the nuances of line and express dynamics beyond pressing a key hard or soft.  And that doesn't even begin to touch on whether the instrument was cared for or abused.

 

Because of the fact that there are a number of people out there who don't understand the voice as well as they should regardless of what style they are singing, many classical and opera people who are responsible for hiring vocalist, shy away from singers who sing multiple styles.  Not because the singer can't sing well in other styles, but because the majority of them don't understand their own voice well enough to be able to be consistent in one style.  Their style becomes their technique and in doing so they shorten the life of their instrument and ultimately their career.  Classical singing, especially opreatic singing, requires an instrument and a musician who not only understand their instrument, but can use their instrument to it's full capacity with excellence.  It is, and probably will remain, the gold standard for vocal ability.  (That's not to say every opera singer has all their ducks in a row either, Lord knows there's a whole trend of using younger more physically appealing singers these days follwoing in the footsteps of hollywood instead of having singers with consumate technique.  But that's a whole different discussion!)

 

Hope that helps, it's an age old conversation that people still argue about.

Chad