What is a mezzo-soprano? This is a question
which has occupied a good many of my thoughts over the past year or
so since an Italian soprano with whom I do much work changed teacher,
was diagnosed as a mezzo-soprano and is now blossoming vocally in a
way hitherto unimaginable. I have therefore witnessed the transformation
stage by stage. But what are the signs? How can you tell what a singer’s
real voice is?
I suppose I had vaguely presumed up till that time
that a mezzo-soprano was a soprano voice pitched about a third down,
but it doesn’t seem quite that simple. For one thing, the category hasn’t
always been recognised, at least not explicitly. In Mozart’s C minor
Mass, for example, there are parts for two sopranos (however, according
to the edition you have, one of them may be labelled "mezzo-soprano").
But the big solo for the lower of the two, while it descends to a low
A, is not suitable for all mezzo-sopranos since its coloratura passages
lie fairly high, and it is sometimes taken by a "normal" soprano
who can "manage" the lower notes. But an ability to "manage"
the lower notes does not necessarily turn a soprano into a mezzo-soprano,
for the part of Fiordiligi in Così fan Tutte also descends to
a low A. But elsewhere a lot of the role goes extremely high and it
has never been suggested that a mezzo-soprano might take it (well, recently
there have been hints that Cecilia Bartoli might do so, but she is a
special case; more of this later). There are also Mozartian parts which
go neither particularly high nor particularly low (Cherubino, Dorabella)
and which can be taken by either, and there are also some leading parts
(Oktavian in Rosenkavalier, Rosina in Barbiere, Carmen) which have been
taken by one or the other; the choice regards the tone-colour one wants
to hear in the part (in the case of Rosina some of the decorations change
according to which voice sings). So, while the actual label "mezzo-soprano"
seems not to date back very far, there has always been a recognition
by composers that voices all had their individuality and the strict
definitions "soprano" and "contralto" ignored the
reality that many singers were not wholly one or the other.
If you hear any female singer rehearsing, you will
realise that women have a faculty which men do not have. When they sing
a phrase over, not projecting the voice but to themselves, maybe to
check word underlay or intonation, they mostly sing an octave down,
at tenor pitch. Even a high soprano can get remarkably low when not
singing "in voice". This of course has no practical application
in classical music since the sound reaches no great distance (in light
music, with a microphone, the technique is actually cultivated). Then
they take a deep breath and project the music in their singing voice,
which usually means an octave up. If the singer is a contralto then
she might sing at the same pitch since she will have rich, natural tones
which take her down to a G or even an F with little need to employ her
"chest voice". Even a soprano can project her voice
on these low notes, but she will have to use exclusively her chest voice.
Singers of light music (those with what we call a "smoky"
lower register) use this technique extensively and actually learn to
carry their chest voice up quite high (think of Shirley Bassey, for
example). Classical singers will tell you this hurts their voice and
they avoid doing it. Occasionally you will hear a soprano doing what
sounds like a Marlene Dietrich imitation as a stunt, by and large, though,
a singer has to train as one or the other and any attempt to run parallel
careers only ends in grief.
But there is also a way of catching some of the chest
resonance to enrich the lower notes. If you listen to a singer like
Christa Ludwig you will hear that even as high as the F above middle
C she catches this resonance which then gives fullness to her timbre
as she descends to her lower notes. This is a very different matter
Philharmonia/Michel Swierczewski