EQUAL-OPPORTUNITY TONALITY.

Byline: CRAIG SMITH 

If you want to get pianist-composer Michael Harrison excited,

talk to him about music in general. (He loves it.) If you want to get

him really revved up, ask him about his views on the tuning system known as equal temperament, ubiquitous in Western classical music. (He's more or less against it.)

And if you want to hear him at his most charmingly messianic, get him going on just intonation -- the term for tuning systems in which musical notes exist in pure mathematical ratios to each other, rather than the unequal ratios of the tempered scale. (Harrison has made it

his life's work.)

The composer plays his 75-minute Revelation for just-intonation piano on Friday, March 13, at the Center for Contemporary Arts.

The Santa Fe New Music event will not only offer the chance to hear unusual music performed by an insightful artist; it just might change and expand how you think about sound, for many a day to come.

"I find people adjust to it very quickly," Harrison said of the sound of his work, speaking by phone from the Other Minds music festival in San Francisco. "I generally have positive audience response. If they are listening from the start of the piece, they're not going to find it 'out of tune,' even after a lifetime of equal temperament.

"It's all there in nature, in natural sounds," he said of the intervals and sonic relationships he uses. "Also, people are used to hearing so many different things these days, we're kind of ripe for a change. World music has played a big role. A lot of world music is not in equal temperament, so people have had a chance to get used to it."

A system for dividing the musical interval of the octave into 12 parts or half steps, equal temperament is one of a number of Western tuning systems that grew out of the sonic rules and ratios discovered by the Greek philosopher Pythagoras. It began to be widely adopted shortly before 1600, and Bach's 1722 The Well-Tempered Clavier is one of its artistic milestones. When we hear a pianist or organist play, or a

symphony orchestra perform, we're generally hearing it in use.

But while useful enough, equal temperament is neither mathematically pure nor capable of projecting the immense range of pitches that exist in nature. As string players and singers know -- and anyone who plays a slide whistle or hears an ocean roar will note -- there are a plethora of pitches to be found between the standard notes of the piano keyboard.

Tuning systems in Indian, Japanese, Chinese, Persian, Native American, ancient Greek, and some Eastern European cultures may sound "wrong" to our ears because we have been trained to accept the practical benefits

and aesthetic shortfalls of equal temperament as the norm. In contemporary music, composers including Terry Riley, Harry Partch, and Harrison's mentor, La Monte Young, are among those who've experimented with alternate tuning possibilities -- Partch, for example, divided the octave into 43 different notes.

For Revelation, Harrison tunes the black keys of the piano to certain pitches and the white keys to others, all of them related by very specific whole-number mathematical ratios. When the instrument is played

in this particular just intonation, the effect is moving and uncanny.

It recalls to some the overtone-rich tintinnabulation of bells, especially when the tonal effect known as "clouds," invented by Young and perfected by Harrison, is in use. The term refers to the acoustic shimmer that occurs when specific sets of pitches are played in very fast, changing

patterns. For Harrison, just intonation lets him bask in sound, while equal temperament only lets him manipulate it.

"When you tune the piano in just intonation, it maximizes resonance. You really hear things you never heard otherwise. People say they hear things that sound like voices, strings, French horns, in Revelation."

The tuning divides each octave into 12 spaced notes, all tuned to overtones of a low F.

Harrison began studying classical piano as a child in Oregon, but music "really became exciting" when his father, a mathematician who loved music, gave him his first music-theory lessons, when Harrison was 12 or 13. "That became much more interesting for me than reading notes off the page." He began improvising and composing and then turned to alternative rock, blues, and jazz. Keith Jarrett is one of his earliest influences and musical heroes.

"Then I got into Indian music" -- which he studied for years under the great master Pandit Pran Nath, who also worked with Riley and Young. "I was singing ragas with tambour as if I'd never heard Western music. And that was around the time I got serious about classical music again. I split my time 50-50 learning Western classical and classical Indian music."

As he explored those two musical conventions simultaneously, Harrison increasingly found equal temperament out of tune to his ears. "The only thing to do was retune the piano. I did it out of pure necessity, seeking beauty in sound and not finding it in temperament. Then I took it the next step" -- the Harmonic Piano, which he devised in 1986. With two sets of strings, each tuned in a different system but equally accessible through use of a pedal, he could play 24 notes to the octave rather than equal temperament's 12. For his performance at CCA, he will use a Steinway grand piano prepared and tuned to his specifications.

That special Revelation tuning came to Harrison in 1999, after he joined fellow composer/performers Riley, Philip Glass, and Charlemagne Palestine at a festival in Rome. Each musician had a Steinway concert grand of his own, lid off, in the high-domed central hall of the Palazzo delle Esposizioni. As each played, the sound of the instrument rolled around and through the space and the listeners, producing a massive and mesmerizing sonic impression.

During the week of rehearsals and performances, Harrison found himself basking in the aural effects he was experiencing, especially in the context of the altered tunings he and Riley had applied to their pianos. The morning after the last concert, he woke up with a new tuning concept clear in his mind that made pure mathematical and musical sense to him.

"Charlemagne influenced the ending of Revelation," Harrison added. "When we were in Rome, he was playing his huge piece with huge sound, and I wanted to emulate that massive wall of resonance. In just intonation, the sound is even more resonant and powerful than it could be in equal temperament."

Revelation has gone through several revisions since its 2001 world premiere; what Harrison will play for SFNM is the most recent version. It is cast in 12 sections that together represent what he calls a sonic journey.

"In a sense, it has the architecture of a raga. It starts slow and

meditative, builds, and ends very rhythmically and dramatically.

It takes 75 minutes from beginning to end, which is about what it takes for a master musician to sing a raga from beginning to end. But it goes through different sections, in a sense like Pictures at an Exhibition.

You journey from one tableau to another.

"I prefer to play it by memory, because the piece originally was performed by memory," he added. "At that time, it was not completely fleshed out. A lot of it was structured improvisation. After performing it a few years, I wanted to notate it as a challenge for myself and let others play it.

"The other thing about playing from memory -- a true mastery of something is where you transcend the act of doing it, so it becomes ultimately about the spiritual experience. Being in the moment so the music can come through you. It's not easy to reach that level to begin with, but it's easier if you're not thinking about the notes. Like an Indian musician performing a raga. It's about the mood, creating a mood."

details

Santa Fe New Music presents Michael Harrison performing Revelation

7 p.m. Friday, March 13

Center for Contemporary Arts, 1050 Old Pecos Trail, 982-1338

$25 at the door, $20 in advance, full-time students $10; advance tickets

available from Nicholas Potter Bookseller (211 E. Palace Ave., 983-5434)

or sfnm.org; caon