On-going arguments about who was/is the greatest opera tenor, soprano, alto, bass, baritone and so on are part of the frustration but also the fun of being an opera buff. To say that so and so was the greatest whatever immediately begs questions, all of which lean on definitions. By "greatest," we need to know whether we are referring to a singer's physical beauty and sex appeal (Corelli, Netrebko), their acting ability (Chaliapin—or almost any Russian, for that matter), the most extreme range (Lauri Volpi, Krauss, famous coloraturas), world-class musicianship (Domingo), highly dramatic and powerful voices (Turner,Giacomini) and so on.
If we look at Beniamino Gigli with reference to any of the above, he does not, sad to say, fare so well. As for looks, he did an excellent—albeit unintentional—imitation of Lou Costello on the stage. His musicianship, by today's standards, was poor. His range was adequate for a tenor, but for the most part he avoided very high notes, especially as he grew older. He was a reliable Bb tenor, with some recorded high C's, in his youth. While he could imply drama, his voice was not that powerful. His acting ability was non-existent. One critic, rather cruelly, once described his appearance on stage as resembling a peasant farmer following a plow. (You need to think about that one a moment.) WHY in the world, then, is he considered to be one of the very greatest tenors of all time? The answer is not hard to discover: he was endowed by nature with what is arguably the most beautiful tenor voice of all time. All else was forgiven.
Born in 1890, Gigli came from an extremely poor family, and received his first education from the local monastery in Recanati, where he sang in the choir as a boy alto. He immediately began to attract attention because of the uncommon beauty of his voice. He was able to get a scholarship to study in Rome, at the Santa Cecilia school of music. He sang in an international contest in 1914, where one of the judges, Alessandro Bonci, himself a brilliant bel canto tenor, famously exclaimed: "At last we have found THE tenor!"
They had indeed found THE tenor. Here is a real bel canto classic, from La Sonnambula:
http://www.youtube.com/watch?v=loZ4ikpx7Gc
Isn't that absolutely ravishing! It is simply one of the most beautiful things I have ever heard. One reaches for adjectives like "divine," in an attempt to describe a voice that beautiful. All the qualities characteristic of Gigli are there: the effortless, floating sound, the long phrases, the exquisite color, and the masterful use of pure head voice. Gigli had an almost invariable technique for singing a song or aria. He always looked for the beauty inherent in the music, and he played first and foremost to that beauty, milking it for every ounce of potential, rarely moving out of head voice or falsetto, and then, typically, toward the end of a piece, pouring out the sound and making a climactic ending with a big high note. (This aria is an exception.) He was a smart man—one can sing forever that way, and he did. He sang continuously from the time he was a child until he was over sixty.
A great part of Gigli's extraordinary popularity during his lifetime derived from the many films he made. Most of what we can see today of him singing is from the movies. The cinema by the 1930's had usurped most of the popular audience from grand opera, with the result that more popular singing styles were less welcome in the opera house at the same time they were embraced by the movies. While Gigli himself managed to stride these two worlds, his heart was with the emerging popular music. Virtually uneducated in anything except music, he was nonetheless a very clever man, and was certainly aware of his shortcomings for an opera audience that was becoming increasingly intellectual. He did not do well outside the limits of melodic and sentimental Italian music. Some of his recordings, such as "Winterstürme wichen dem Wonnemond," or "Il Mio Tesoro Intanto," are just plain silly. He sensed, however, a big opportunity in films, and this turned out to be a brilliant move on his part, for several reasons. First, it gave him a huge audience that would never have seen him in an opera house, and second, films were—curiously enough—often able to show his slight acting skills to advantage by the clever subterfuge of letting talented actors play off him, so that we look at audiences, love interests, dramatic complications, etc. while he is singing. This keeps our ear on him, and our eye on better actors. A good example is the film "Non Ti Scordar di Me." He sings the title song in front of a curtain (he portrays an opera singer in the film) while his beautiful love interest sits in the front row, weeping. We see much more of her, but we hear the unequaled voice of Gigli:
http://www.youtube.com/watch?v=8tk3Eb_zx4o&feature=related
In spite of his penchant for movies and sentimental favorites, however, he did not abandon the operatic repertoire. Quite the contrary. He was everywhere renowned for his opera performances, both in person and on record. Here is what is clearly one of the best recordings ever of Nadir's aria from "The Pearlfishers":
http://www.youtube.com/watch?v=Pn5XnM5Fg9E
What can one say? It is illustrative to look at some of the viewer comments below these videos. They are very consistent and endlessly admiring, even today, of the nearly inexpressible beauty of that voice. Tenors come and tenors go, but Gigli is forever; eternal evidence of the fact that while admirers of the arts may be moved by many things, they are moved by nothing quite so much as by beauty.