It was grand to hear Martina Arroyo, one of this country's truly fine singers, at the Kennedy Center again last night, after a hiatus of 11 years.

Arroyo's New York appearances have been rare in recent years as well, though she has been busy on opera and recital stages in Europe and South America. Her voice is just as one remembered, a large, beautifully focused soprano, with an even range--wonderfully suitable for the heavier parts in Verdi, for which she is best known in the music world. Her stage presence is assured and vibrant, and her figure is becomingly more slender.

Last night's program, sung in the Terrace Theater, consisted mostly of songs by Schubert, Richard Strauss, Faure' and Turina. The five Schubert songs, in particular, require an intimacy that sometimes comes with difficulty to singers of Arroyo's vocal amplitude. She brought to them tonal and intonational accuracy and a sure sense of changing moods--from the grim compulsiveness of "Gretchen am Spinnrade" ("Gretchen at the Spinning Wheel") to the sprightly ingenuousness of "Die Ma nner sind me'chant" ("Men Are No Good"). If the sound was sometimes a bit too full to seem intimate, still Arroyo is a very intelligent artist who is on her way to mastering this side of musical art. She knows what she is doing.

The Strauss sometimes allows a grander sound, as in "Cecily," where Arroyo let her huge voice go, quite thrillingly; and in this song accompanist Henri Venanzi played especially well. One case where she scaled down to just the right level was in Strauss' little "Einerlei" ("Uniformity"), which was a delight. Faure''s little "En prie re," which is a child's prayer, was sung with soft purity.

For those of us who just had to have some opera, there was an Arroyo staple, "Ernani, involami" from Verdi's "Ernani." The performance had the same stamp of authority as when she sang it at her previous concert at the Kennedy Center, a benefit with Placido Domingo in 1972. Her ringing coloratura and tonal command reminded one how fine a Verdi singer she is. Now if only she were back with the Met, and had sung Leonore in the performance of "Forza" last Saturday, it would have been an altogether more exciting affair.