The six programs that the Contemporary Music Forum presents at the Corcoran each season are the most uncompromising exercises in the rigors of advanced idioms that Washington audiences face. The 20th Century Consort is a puppy dog by comparison. And the Theater Chamber Players are downright patsies.

Last night's concert by the Forum was no exception, though one member of the audience attending for the first time remarked during intermission that he had come because a friend told him that the program was "easier than most" -- for the players and the listener.

That was, it seems to me, because two of the five works had dimensions of entertainment, not that there was anything easy about either.

The most striking was a set of luridly expressionist songs (if that is quite the word) called "Speeches for Dr. Frankenstein," set to texts by Margaret Atwood from her book, "The Animals in That Country." The composer was the Canadian Bruce Pennycook.

The songs are for soprano and an elaborate tape of voices and synthesizer. First sung in 1981, they include moments that are close relatives of Scho nbergian Sprechstimme for ominous lines like "What equation shall I carve and seal in your skull?" But there are also lyric musical lines that soar to imposing highs, as in "I am the universal weaver."

Part of this performance's success can be attributed to the searing, committed singing of Pamela Jordan. But also, for all the difficulty of the musical idiom, the composer showed a considerable sense of drama and, yes, theater. The poems, as well, are powerful. The other moment of entertainment came in a wry, Cage-like Jacob Druckman work for solo clarinet and tape, "Animus III." Written in 1969, it sounds about as much like the Druckman of today as Boccherini does.

Basically, it's a gag, in which the infernal racket on the tape (which sounds like a blast furnace married to a nuclear attack) presumably blocks out a concert and speech given by the solo clarinet, in this case the delightful Ronald Aufmann.

But just so we wouldn't get too relaxed for a Contemporary Music Forum audience, they put us on our musical toes with the other stuff, especially the important and incredibly difficult piano piece "Sequenza IV" by Luciano Berio. This is a major work from the celebrated composer during his densest period (1966). Barbro Dahlman played with considerable sensitivity (if that is the word).

Also on the program: Dinu Ghezzo's austere "Music for Flutes and Tape" and Claude Frenette's foggy "Infrarouge E 4."