The New York Philharmonic has made a brave, ambitious stab at creating a new music festival under the umbrella title of ''Horizons'' - 10 concerts in nine days, 40 composers, 45 works.
At this writing I have reached the halfway point of the marathon. It has been stimulating, entertaining, sometimes tedious, occasionally irritating - all part of the concept of ''The New Romanticism - A Broader View'' by Jacob Druckman, a composer and ''Horizons'' artistic director.
There has been a good deal that hardly sounds like new romanticism - be it established works or even new ones. But at its best, the music has been exciting and communicative, which are qualities too many composers shied away from a decade ago.
''Horizons '84'' will have had five concerts performed by the New York Philharmonic proper (which I will discuss next week when I have heard the rest of the programs). Of the remaining five, two are devoted to ''Recitals: The New Virtuosity,'' the rest to aspects of music and computers.
The recitals were given mainly by composers performing their own music. The most overtly exciting proved to be Diamanda Galas. This virtuoso singer uses microphones, live signal processors, and her voice to create a sound-picture of uncommon variety, timbre, texture, and subtext. Her compositions are distinctive cries of pain, anger, fear, tenderness, passion. Her use of a good soprano voice of indeterminate size is ultravirtuosic. One might observe that the pieces she offered outlasted their welcome, but this is so often the case with music at these events.
Talking during a piece was big this year. Trombonist Stuart Dempster - after playing a tape of his composition recorded in a 14th-century French abbey and punctuated by live ''insertions'' - went on to do a silly-fun theater piece by Robert Erickson. This involved a costumed Mr. Dempster reciting Gen. Douglas MacArthur's retirement speech at West Point into his trombone.
Another such piece was offered on the same program by double-bassist Jon Deak - his own elaborate comedic work involving a recitation of passages from Hesse's ''Steppenwolf,'' accompanied by imaginative sound effects created by playing his double bass, and rapid management of various props. The presentation lies somewhere between art and National Lampoon humor, but it is entertaining. Mr. Deak also performed a Kenneth Gaburo work that asks the soloist to sigh-cluck-burp-hum-gasp while he plays-taps-plucks a wickedly tough bass part - a gimmicky approach, but unquestionably ultravirtuosic.
Flutist Robert Dick talked into his bass flute for his own ''Glimpse From the Blimpse,'' to little meaningful effect. He was better showcased in his ''T EQUALS C10,'' translated as ''T might equal C to the 10th power.'' His ability to conjure unearthly sounds from the bass flute proved consistently commendable.
Not so commendable was Dean Drummond's music for his enormous zoomoozophone - his own intriguing mallet instrument that looks like a huge xylophone with tubes rather than metal bars, using 31 pitches to an octave rather than 12. It is extravagant in overtones, which Drummond dearly (and tediously) loves. And vocalist Joan La Barbara loves those overtones, as heard in her uneventful piece for Drummond, his players (who call themselves Newband), and her voice. She then regaled us with 32 minutes of her own voice-only music - live and on multitrack tape. Neither piece won her many converts, despite the unusual sounds she can make with her throat.
The computer programs had more musical substance - be it Michael McNabb's evocative timbral/textural tape exploration entitled ''Dreamsong'' or Laurie Spiegel's ingratiating first movement of ''Music for Dance.'' Charles Dodge's understated, elegant, at times eloquent ''The Waves'' took a synthesized taping of Miss La Barbara's voice and intertwined it with the live Miss La Barbara on stage.
In a chamber music program, a Iannis Xenakis piece, ''Khal Perr,'' for brass quintet and percussion, employed computers in the composing process. It is typically harsh, angry, steely Xenakis, but it had passion and a sense of mission. On an American Composers' Orchestra program, Charles Wourinen conducted the world premiere of his own ''Bamboula Squared.'' It was full of drama, excitement, beauty, a handsome command of orchestration, and a stunning meshing of an elaborate computer tape that consistently expanded on the tones and overtones of the orchestral palette.
The variety of pieces offered was almost dizzying. The best ones communicated something to the audiences, and the they responded voiciferously.
There are serious limitations placed on interpretation: To remain in synchronization with the tape often becomes the principal challenge of the piece. But clearly, composers are now reaching out with distinct voices, and seeking to refine those voices to reach an audience rather than just a few other composers.
Unfortunately, the word is not really out yet: Avery Fisher Hall was more than half empty every night. But the best works on these five programs proved that there is hope for new music after all, whereas five years ago the future seemed grim indeed.