Boston — Angels take heed. Overwhelming earthly demand has brought Swiss harp sensation Andreas Vollenweider and his unique brand of electro-acoustic music to the United States for a 12-city tour. Besides accolades from mood pianist George Winston (''truly an inspiration''), and singer Carly Simon (''stirred to the core''), Mr. Vollenweider says he has received more letters from the US than from Europe, where 159 of his last 160 concerts were sold out. His latest album, ''Caverna Magica'' was voted Pop Album of the Year by Audio magazine (Germany) - edging out Michael Jackson's ''Thriller.''
''I didn't want to come,'' says this curly-headed Peter Frampton look-alike. He has already thrilled New York, Boston, and Midwest audiences with music that runs the gamut from Latin to oriental and from jazz to soft rock.
''I knew that this country is so big that you get lost definitely if there's not a certain need for what you're doing.''
But there has been, and people love it. What the 31-year-old, Swiss German musician does is weave intricate tapestries of pop, jazz, and classical sound on a highly stylized harp complete with customized damper and microphone hookups for each of 47 strings. While plucking staccato melodies and improvisations with the superlong fingernails of his right hand, he pounds out bass and rhythm with the palm of his left hand on the longer strings. The number of effects possible with both hands pounding, plucking, strumming, and raking is astounding.
''No company believed in this music when I first came up with the idea,'' says the Zurich resident, whose father, an eminent organist, taught Andreas piano and German flute as a youngster. ''They were not just laughing, they were almost throwing me out of the offices.''
That was about four years ago. Now, Mr. Vollenweider's two current albums have both gone gold, he's written scores for 50 films, and he has a following that is beginning to grow on both sides of the Atlantic.
''The letters people write are very special, written a very personal way. They are very long and hard to answer,'' he says.
Called psychedelic, free-floating, atmospheric, and ethereal, Mr. Vollenweider's music is mostly upbeat, affirmative. Some critics have said it lacks depth, even that it approaches Muzak - a term Mr. Vollenweider doesn't shy away from. ''The heavy melody is always missing, that's why it can be used as Muzak,'' he says. ''We shouldn't overstuff our sensitivities with heavy metal sounds. If my music is light, it comes from the light,'' he continues, saying the reason he composes is to give back to his listeners all the good things that have happened in his life. He told one interviewer when asked about his film scoring: ''I quickly learned I can't make music for thrilling, scary scenes.''
Not that Mr. Vollenweider uses the instrument like the angels - long, classical strumming associated with heavenly themes. He almost always avoids that.
More to his style are variations on tango, rhumba, bossanova, Afro-Cuban, East Indian, and Caribbean rhythms. But he says he has never studied them consciously, nor ever taken a formal music lesson.
Not only has he pioneered a new sound, Mr. Vollenweider has pioneered a new technique. For this interviewer, he holds both hands out, fingers fully extended toward one another. ''This is my technique,'' he says, sitting erect as if he were hugging his harp. ''Not like this,'' he says, gnarling each set of fingers nearly into a fist to show how the classical harpist is trained. ''Usually harpists aren't so happy people because most of them get tired of the way (the harp) is played, and you get cramps. It's not a healthy instrument.''
A member of the band ''Poetry and Music'' from 1972-78, Mr. Vollenweider experimented with many kinds of instruments before finding the one that suited his personality best.
''I saw a small one and I bought it just like the other instruments, and neglected it for a while ... and after a while I started to modify it. Then I got more and more interested.''
The appeal for him is the instrument's enormous scope. ''I was after this full range sound. I had modified guitar. I had modified piano. But the range of this instrument allows you to play almost the whole range of a band out of one instrument and finally out of one body.''
The current tour features his backup foursome playing everything from drums, flute, and saxophone, to keyboards, xylophone, and various other percussion. Performances are improvisational but highly polished, with uninterrupted sets that flow from one motif to the next. One key word is experimentation.
''You have to be inventive yourself. You have to be a seeker. There are avoiders and there are seekers, collectors, picking berries and mushrooms they hunt. I'm a seeker.''
Mr. Vollenweider and friends will perform in Austin, Texas, Nov. 1; Albuquerque, New Mexico, Nov. 2; Los Angeles, Nov. 3; and San Francisco, Nov. 4. Call CBS Records (212) 975-4763 for more information.m