I have been taught classical singing since 8 years ago. My voice is heavy, I sing in choir and vocal quartet as an alto. I have two vocal problems:

1) I can’t sing piano and pianissimo in notes above E an octave above middle C. In fact I can’t keep my throat open to sing piano and pianissimo and I need to sing forte to produce sound in high tessitura! (I can sing bocca chuisa up to high C without pain!)

2) Sometimes I can’t control my vibrato during singing, specially while singing piano.

Is it true that singing pianissimo is like singing falsetto and there is no resonance?
How can I learn a correct pianissimo without breathiness?

This set of questions on singing quietly is complicated, because the answer depends on exactly what you are doing when you sing.

If you have difficulty singing quietly above that E, and your throat closes up, it is likely that your vocal tract is too long for the notes and tones you are trying to achieve. Around that note there is a “gear change” for female singers. Your larynx is probably being held down to add darkness and depth to your sound (probably with the tongue muscles pushing down from above). You will end up “weightlifting” with your voice to get higher or softer, causing your vocal folds to work harder than they need to. This may also cause you to have a more unstable vibrato as the vocal mechanism is under intense stress being held down while singing high and soft.

From your description of the two problems, I would recommend exercises to raise the back of the tongue. This will allow your larynx to rise slightly at this crucial pitch (E5). I would also recommend you practise tilting the thyroid cartilage without lowering the larynx. ‘Tilting’ and holding the breath back should give you a clearer, cleaner sound and reduce the breathiness.

Our book of voice exercises This Is A Voice contains several exercises that would work well for you – exercises 4, 5 and 6 (stretching the back and releasing the root of the tongue), exercise 73 (the whinge setting – to tilt the thyroid cartilage and stretch the vocal folds), and exercise 78 (Vowel tuning to “e”).