He was born Jose Antonio Ruiz in 1958, to a couple of Puerto Rican origin, in Paterson, New Jersey, a decaying industrial city near New York. He began singing with amateur groups at the age of nine and by the time he was in his early teens had recorded a demo disc with a local group, La Orquesta Nueva. This was the period when New York-based musicians of Cuban and Puerto Rican extraction were establishing a hard new musical blend, traditionally based but developed in urban America, that rapidly became popular internationally under the tag of "salsa".
In 1974 Ruiz's mother, Hilda, separated from his father and they moved to the Puerto Rican town of Mayaguez, another working-class conurbation on the western end of the island.
Hilda Ruiz seems to have been a classic exponent of the American art of pushing offspring into show business. She repeatedly took her son to the gigs of a Mayaguez-based salsa band La Solucion and thrust him on the bemused bandleader as a future star singer. Meanwhile, Frankie learnt the band's entire repertoire, removing any chance of refusal on the grounds of lack of experience. Eventually, perseverance paid off and he was taken on as a vocalist.
After three years with La Solucion, Ruiz was hired by the veteran bandleader, trumpeter and producer Tommy Olivencia, one of the most dynamic creative forces working between Puerto Rico and New York, noted for a keen commercial sense but also for a penchant for bringing along artists with a flair for the soulful art of the true sonero (a singer of the traditional Cuban son style of music).
Ruiz's period with the Olivencia band constituted another successful three years, marked by three hit albums, the third of which, Celebrando Otro Aniversario ("Celebrating Another Anniversary", 1984), also spawned a hit single "Lo Dudo ("I Doubt It") which brought Ruiz fame in his own right.
"Lo Dudo", a version of a romantic Mexican ballad, also marked the advent of a new trend in salsa, the transposition of light romantic melodies from other pop genres into salsa arrangements. This tendency, which is still popular today, was to make the careers of a crop of new young vocalists, including Ruiz, but also attracted scorn from other musicians and aficionados, who saw it as lightweight and vapid ("salsa monga" or "limp salsa" is the term one prominent old-school musician uses).
By the late Eighties, a second development to this style was boosting record sales: the incorporation of mildly sexy lyrics, leading to the creation of the new term "salsa erotica". Titles like "Devorame Otra Vez" ("Devour Me Again") by Lalo Rodriguez, with its celebrated reference to moistened bed-linen, were the great hits. Ruiz's most prominent contribution was "Desndate Mujer" ("Undress, Woman").
Although Ruiz's youthful voice and song choice enabled him to excel in the new erotic/romantic mode, his background as a serious sonero and his use of high-quality backing musicians kept the respect of traditional salsa lovers and he ended the Eighties among the top Puerto Rican American artists, his debut album Solista Pero No Solo ("Soloist But Not Alone" 1983) one of the decade's biggest hits.
By this time Ruiz's consumption of drugs and alcohol was also making itself apparent. The journalist Josue Rivas recalls interviewing Ruiz in his hotel room early one evening at the beginning of the Eighties. It was hours before he was due on stage at the Red Parrot Nightclub in New York, according to Rivas, but Ruiz was already smashed. He would start drinking rum and beer as soon as he got up in the morning. Between 1988 and 1992 he served two jail sentences for possession of crack cocaine.
He continued recording successfully throughout the early Nineties, releasing hit albums such as Mi Libertad ("My Freedom", 1992), Puerto Rico Soy Tuyo ("Puerto Rico I'm Yours", 1993) and Tranquilo ("Easy", 1996), but his health deteriorated considerably from 1996 onwards and he spent periods in and out of hospital. Latterly, he claimed to have given up drugs and to have discovered religion: of the three new songs he recorded earlier this year to be included on a new album, the one attracting most air play on Latin radio at present is "Vuelvo A Nacer" ("I'm Born Again").
Jose Antonio "Frankie" Ruiz, singer: born Paterson, New Jersey 1958; married (one son, two daughters); died New York 9 August 1998.