My father passed away with an unresolved mystery when it comes to technique. We would spend hours listening to Caruso and Bjoerling, talking about what it was in their high notes that was different. What made their squillo, the high ringing quality, or Singer’s Formant different?
Years ago, I started to train myself to actually hear the harmonics in my voice and learn how to strengthen them. I started to hear things in recordings of my favorite tenors that I could never quite put my finger on before. I tried to crack the mystery my dad and I never resolved together. I could hear that the ringing quality of the high notes of tenors from before the 1940s was different than that of their modern counterparts. I would attribute this to recording equipment, to changes in overall approach, but I really couldn’t figure what exactly I was hearing.
I found the solution thanks to reading the writings of Richard Miller. In his books, for the first time I saw a representation in graphic form of the harmonics in the voice of some of my favorite tenors; and I noticed very clear differences when it comes to what in Italy we call “squillo” – Singer’s Formant.
Being the science geek that I am, I found and figured out a way to use software to isolate the sounds of these harmonics; and that is when I found that halfway through the 1900s a shift in tenor vocalism occurred in the approach to resonance.
The high ringing overtones of the tenor high voice, can be significantly strengthened when certain conditions are in place. I am not going to go into the science of this, but will say that when the voice is efficiently produced, or when the sound is very focused, and when the larynx is relaxed low, and the throat is relaxed and in a yawn position – the squillo, or Singer’s Formant, eventually can develop. As the tenor’s ability to sing with appoggio increases, the squillo gets stronger.
I like to think of this Singer’s Formant as a little microphone implanted in our throats that picks up and amplifies only sounds between 2,300 hz. and 3,500 hz. Now to my point… The tenors in the early 1900s, and a handful after 1940, all enhanced the lower part of that 2,300-3,500 hz range. Typically the harmonic strengthened was the 5th. Tenors after the mid 1900s amplified the upper part of that frequency range, usually the 6th and 7th harmonics. What this means is that the ringing squillo of tenors from the early 1900s was lower in pitch compared to those that came after.
Finally I had figured out what I was hearing. Caruso’s and Bjoerling’s squillo was a lower pitched squillo compared to tenors like Pavarotti, Corelli, Tucker, Del Monaco, and others. Here is a clip where I compare two titans: Corelli and Lauri Volpi, two great Manricos from different times. I will show you the different pitch enhancement of their squillo. Corelli’s ring is higher pitched compared to Lauri Volpi’s.
Here are graphs showing what you hear.
The difference in the pitch of their squillo confers different qualities to the sound. The modern tenors are a bit brighter sounding, while the old timers have more of a dark velvety sound.
For a very long time I tried to understand how to get to the 5th harmonic enhancement like Bjoerling and Caruso had. I could not. I tried singing more toward an OO, like they do, to see if the vowel would track the harmonic, but I still could not get it. I kept strengthening the 6th and 7th. Many modern tenors singing an OO vowel continue to enhance the 6th and 7th harmonics. Why wasn’t I able to do it?
I will just give you the answer of many years of study… (1) I carried too much chest voice up, and (2) I had not yet developed the OH-EH mix – voce magra phonation, and (3) I was singing with canna aperta. Think of the sound as having a sort of tube going through the larynx and up to the mask. This tube can be wide (canna aperta) or it can be narrow. If you sing the passaggio in an OH-EH mix in thin voice, and you keep ascending toward the top, aiming to continue the forward ringing quality of the passaggio. The air feels like it is moving through a narrower tube in the throat. It’s not a muscular tightening, or at least I don’t think so. It feels like the space where the air passes through is narrower, but the throat is not constricted. It is as though the sound were pressing inward toward the larynx. The sound is squished, not the throat.
If you cough gently, you feel where your vocal folds are. When one sings with the OH-EH mix in the passaggio, the tongue is oriented forward, and my sense is that the tongue is not pressing on the larynx. The OH-EH mix really narrows the sound in the passaggio, and the voice feels like it is striking the maxillary sinuses. It’s a feeling of really thin edge. If this position is taken up past the passaggio without changing, and the lips are brought forward, the sound will strike more toward the frontal sinuses and the cheeks. But remember, that is the consequence and not the cause. You can’t force your voice to go there. It goes there because of the way the cords are working… it is the thin cry, the tongue forward thanks to the OH-EH mix, and this narrowing of the vowel. The sound is now compressing inward toward the larynx. It feels like the voice has reduced the width through which the air can pass. The voice compresses, not the muscles… The vowel gravitates toward an OO because of this narrowness. You can sing an AH if you want, but if your sound is narrow, it will come out OO.
Here is my humble attempt at imitating Caruso, and I am able to tune the 5th harmonic here as I imitate him.
These are the graphic readouts for the Bflat in La Fleur from Carmen, with Enrico Caruso and my humble imitation. You will notice from the graphs that the 5th harmonic is particularly strengthened; and also a quick drop of harmonic intensity occurs after the 6th harmonic. The result is a very compact sound with very little higher, noisier harmonics. The sound is not as bright, but the ring is intense.
Caruso’s vowel is very pure!!! It’s absolutely, perfectly efficient because the thin voice is balanced with the breath pressure so exactly as to produce a completely efficient sound. Compared to my attempt, Caruso, besides having an infinitely better quality voice, also has stronger squillo. I suspect he is able to harness the breath with thin cords much more effectively.
Here is Del Monaco. You will notice very powerful squillo, but as you can see from the graph, his power is in the 6th and 7th harmonic, and not in the 5th.
Here is Gigli singing the B natural from Pazzon Son, Manon Lescaut.
… and last, but not least, let me compare two high notes, one by Caruso, and another by Tucker. Both have powerful squillo, but as you will hear in the clip, the harmonic being enhanced is different. Caruso enhances the 5th and Tucker the 6th. Why the difference in harmonic selection?
Li Vigni – Ou se divine la presence, High C – 5th Formant Dominance (old school if I may say so myself)
The lower harmonic selection requires:
- cry mechanism, less chest voice
- a continuation of the OH-EH mixed vowel intention (notice Caruso’s note right before the top. It is a perfect OH-EH mix)
- compression of the vowel vibration inward toward the cords, or feeling of narrowing of the imaginary tube through which the air passes through the larynx… the sound squishes the space inward toward the larynx.
The Higher harmonic
- carries more chest upwards
- has a wider imaginary tube through the larynx
- the sound leans into the larynx more
- the soft palate is pulled upward very much
The secret of the older high note sound lies in not letting the compression of the sound stop the air. While the secret to the other is to think very much open throat sound.