Andrea Velis knows his way around New York's Metropolitan Opera. He has mastered its labyrinth of corridors and rehearsal rooms. He is an expert on almost every opera it has presented during the past three decades. He hobnobs easily backstage among its staff and singers. Mr. Velis is not, however, some affable administrator. Nor is he a savvy tour guide. And he certainly is not the phantom of his opera house. He is, rather, one of an unusual breed of singers who have remained with a single opera company over a professional lifetime. Since arriving in 1961, Velis has become the Met's most prolific player of supporting roles, from the witch in ``Hansel and Gretel'' to a multitude of characters in ``The Tales of Hoffmann.''
In June, Velis joined the Met's three-week tour of Japan, and it should come as no surprise that the tenor logged more performances than any other member of the company. He already holds the record for most appearances in a single season and has amassed more than 1,800 during his Metropolitan career.
More than achieving numerical feats, Velis has become one of the few Americans to make a career of comprim`ario singing - performing operatic ``character'' roles.
``When I started, it was very wishy-washy as to who did what role,'' Velis recalls. Smaller parts were either given to European specialists or treated as way stations for young artists on the rise.
That situation has changed during the course of Velis's nearly 30 years and more than 60 different roles at the Met. ``We're actually the heart of the company,'' he insists, referring to the handful of fellow comprim`arios. ``It's like having a base on which to build a production. You know it's always solid, and it's always there.''
An important part of his job, Velis says, is developing the dramatic as well as the vocal side of his characters. To this end, he employs his own acting coach and even studies videotapes of the legendary soprano Maria Callas, with whom Velis performed in the 1960s and from whom he learned to ``untime'' his drama.
``We're not free to act as we wish; we're dramatically restricted to the musical bar lines,'' Velis explains. ``But if you watch how Callas acts, she goes against the music.''
Some of Velis's parts are completely spoken, such as the cranky Duchess of Crackenthorpe in ``La Fille du Regiment.'' And his favorite role - the Simpleton in ``Boris Godunov'' - finishes on a dramatic rather than a musical note. This character virtually upstages the newly crowned Boris by accusing him of murdering the rightful heir to Russia's throne, a moment that is not lost on Velis, who brings the curtain down with a haunting, Kabuki-like movement.
``The Simpleton has to express the pathos of Russia's past and present, and the horror facing Russia in the future,'' he notes. ``It's a little scene that has to be big, and one little person dressed in rags has to create it.''
Velis also covers for less dramatically inclined lead singers. ``So many of them are just voices, and it makes it difficult, because they don't react on stage,'' he says. ``I have to adapt to make it look as if they are acting.''
Velis has played everything from courtiers to crackpots to an assortment of women. On the summer's Japanese tour, he divided his time between Curzio, the manipulative lawyer in ``Marriage of Figaro,'' and Spalanzani, the scheming inventor of mechanical dolls in ``The Tales of Hoffmann.''
Although Velis did not start his operatic career with these destinations in mind, he took up comprim`ario singing as soon as he joined the Pittsburgh Opera in his native Pennsylvania after studying voice for five years at the Academy of St. Cecilia in Rome.
``I was told I was a good actor and that there might one day be a place for me at the Met,'' he remembers. When that day arrived in 1961, it took only a 15-minute audition for the Metropolitan's general manager, Rudolf Bing, to hire him on the spot. In the following season, Velis set his record by singing in half of the company's performances, and since then he has made between 50 and 100 appearances annually.
Despite his second billing in most productions, Velis has won his share of recognition. Parts like the Simpleton or the Witch dominate their respective operas, and many of his roles often steal the show anyway.
``I'm even approached on the street by opera buffs who say they'll never forget some of my roles,'' Velis says. ``It's flattering, since I'm not that recognizable because of all the makeup I wear on stage.''
Velis prefers his line of work to taking center stage. ``Most lead singers are busy producing sound, and their roles are written to allow them to sing,'' he observes. ``But character roles are written with a wonderful charm. They're always more interesting.''
Staying in one place has also appealed to Velis. ``I love the feeling of being at home in an opera company, and I'm at home here,'' he admits, adding that today's opera stars are ``jet-set singers and have to fly around like crazy.''
At the same time, his career at the Met has imposed some unusual obligations. When Velis is not singing, he is usually ``on call'' and must spend his evenings within 20 minutes of the opera house in case he is needed to fill in. During the Met's seven-month season, he cannot leave town without special permission, a situation that has limited any additional singing opportunities to neighboring organizations such as the New York City Opera and the New York Philharmonic.
The middle-aged Velis has no plans to stop singing anytime in the near future, noting that his predecessor at the Met retired when he was 72. Meanwhile, Velis is already aware of the legacy he has been creating, and he notes that ample opportunities exist for young singers, even those still in music schools, to follow in his footsteps. ``I like to think that my career has inspired others to look at these roles more seriously,'' he says.