Four-year-old Rachael Blake sits at the piano, her long, golden hair pulled back in a ponytail, her tiny fingers playing the notes of ''Lightly Row.'' What is remarkable is the musical tone she evokes. At an age when many youngsters pound harshly on a piano, Rachael shows the sensitivity of a pro.
Beautiful tone is one of the basics of the Suzuki method by which Rachael is learning. Developed by Dr. Shinichi Suzuki in the 1950s, and brought to the United States in 1964, this method is now used by hundreds of thousands of music students worldwide to learn piano, violin, cello, viola, and flute.
Dr. Suzuki prefers to call his method the ''mother tongue'' approach. He bases it on the idea that every child in the world learns to speak his or her native tongue perfectly, simply by listening.
Dr. Suzuki reasoned that children exposed to good music at an early age will develop a good ear. Then, with proper training, they'll be able to translate that into a beautiful sound on an instrument.
Mrs. Evelyn Rubenstein, a well-known piano teacher in St. Louis and a member of the music faculty at University of Missouri-St. Louis, where she originated the piano proficiency course for music education majors, does not use the Suzuki method. But she told The Christian Science Monitor, ''I am impressed with it, because I've seen the results. At a demonstration I attended, some very little children and some older students, too, performed very well. Many of them had taken prizes in competitions.
''One of my piano students belongs to the Suzuki violin group. They learn to play the instrument correctly; their ear is attuned. They can accomplish more because they don't have to spend time at the beginning learning to sight-read; they can play beautiful things.
''But they do learn to read notes eventually.''
If tone is the goal, listening is the method. Rachael's mother plays tape recordings of songs her daughter will learn on an endless tape, replaying it as often as 50 times a day as Rachael plays with her toys, eats breakfast, or drifts off to sleep.
By the time Rachael begins to learn a new piece on the piano, she can already sing it in her head and can correct her own mistakes.
Christine Blake, Rachael's mother, thinks the Suzuki emphasis upon listening has had ''a profound effect on all of us and on Rachael in particular. Rachael listens to me better. I think she absorbs adult conversation better, and I feel it will help her when she goes to school.
''Now when we go on walks, I notice that Rachael listens for bird calls. She picks up sounds quicker.
''While I'm fixing dinner, Rachael listens to her lessons. She can put the tape on herself. But she also asks for 'home lessons' - periods when she practices while I sit right beside her.''
At her formal lesson, Rachael's teacher sits on one side and Rachael's mother , holding Elise, Rachael's baby sister, sits on the other. Parent involvement is an important aspect of the Suzuki method. The baby is already learning by listening.
''Scramble it,'' requests the teacher, Margery Forbes of Exeter, N.H. Rachael plays ''Lightly Row'' with the phrases interchanged, the last phrase first, the first phrase last.
This kind of practice trains the children to be able to start at any point in a piece, so that if they make a mistake, they can easily pick up and go on.
A Suzuki-trained musician is no more afraid of striking a wrong note in playing than a person would be afraid of saying a wrong word in speaking.
''It's a good method for young children,'' says Ron Bentley, coordinator of instrumental studies at Berklee College of Music in Boston. ''Sight-reading is one of the problems. When they need to read notes, they have to 'go back to kindergarten' on that. But Suzuki-trained musicians who start at a young age seem better equipped and more successful at performing . . . their ear-to-hand relationship is developed very well; they have a sense of pitch and tone that some students using other methods never attain.
''Another good thing about the method is (that) playing together in groups is a heck of a lot more fun,'' he said.
The Suzuki method is full of games. At the end of Book 1 Mrs. Forbes has a special lesson in which she reads a story containing the names of all 19 pieces in that book. As she announces a title, the child plays the piece, until all have been played through. Repeated playing of former pieces is part of the method.
According to one violin teacher, Louise Wear of Durham, N.H., who has studied in Japan under Dr. Suzuki, the founder of this method is ''always thinking up little tricks for the children.'' She recalls, ''He would appear in the morning and say, 'I have a new idea, I am so excited.' '' She describes him as a very small, very spry man with a childlike attitude toward life.
Louise Wear switched from traditional teaching methods to Suzuki in 1966, shortly after Dr. Suzuki toured the US with 10 Japanese children, ages five through 13, who electrified the music world with their remarkable performances of such pieces as Vivaldi's Concerto in A minor.
Eric Pritchard, a neighbor child, was Mrs. Wear's first violin pupil after she switched to the Suzuki method. He worked with her from age 5 until he was l4 , when he went to the New England Conservatory of Music in Boston. He graduated from the University of Indiana in June of this year and is now studying at the Juilliard School in New York while playing first violin for the Alexander String Quartet. Eric has performed solo with the Boston Pops.
Eric's mother credits Louise Wear with getting Eric started. ''He had the most happy adolescence,'' Mrs. Pritchard says. ''He practiced 45 minutes every day. He had a paper route and played baseball, which he loved.''
Now Mrs. Wear trains violin teachers at institutes throughout the US during the summer months. ''The main points of the Suzuki method are start early, parent involvement, lots of listening, lots of repetition, and take one step at a time,'' she says.
Using the step-by-step approach, all the children learn the same pieces, with each piece teaching a certain skill. ''Nothing is hit or miss,'' comments Mrs. Wear.
She doesn't mind listening over and over to ''Twinkle, Twinkle Little Star'' (the first Suzuki piece). ''I'm not listening to the piece of music - I am listening to the child's development,'' she says.
One advantage to having all children learn the same pieces is that they can play together at concerts. At the first lesson, the child is trained to bow low from the waist, hold that position long enough to whisper ''hippopotamus,'' then slowly rise up to the applause of teacher and parent. Such training helps children perform with poise at an early age.
Concert manners are stressed at frequent group workshops where small groups of children play with and for each other. Four or five times a year, Mrs. Wear's pupils perform concerts for parents, friends, and the general public.
A number of summer institutes offer special week-long sessions for Suzuki teachers, parents, and pupils. At the annual American Suzuki Institute at Stevens Point, Wis., several thousand children take part in the final concert.
At the beginning of the concert, all children with the same string instrument sit on the stage. The most advanced pieces are announced first, and only a few children stand up to play. As less advanced pieces are announced, more children stand up, until all the children in unison perform the ''Twinkles.'' Violin, cello, viola, and flute students play in ensembles, but piano students play solo at such gatherings.
At a national concert some years ago in Japan, 3,000 children performed in unison on the violin, a sight that brought tears to the eyes of world-renowned cellist Pablo Casals, a special guest.
In the US the organization that runs the institutes is the Suzuki Association of the Americas Inc. (319 E. 2nd St. Muskateen, Iowa.) Suzuki has approved 3,488 teachers in many countries, including the United States (with the largest number by far), Canada, Brazil, New Zealand, Denmark, West Germany, England, Indonesia, and others.
Doris Preucil, president of the association, says there is no way to compute the number of pupils learning by the Suzuki method around the world. Some teachers in the US do not belong to the SAA, yet use the Suzuki books. She estimates the number could be as many as 200,000 worldwide.
Many traditional teachers have objections to the Suzuki method, but to Doris Preucil, the proof is in the pudding. ''Of the next generation of young musicians, many have come from Suzuki programs,'' she says. ''You see the quality of the playing, and this cannot be denied. And you see the happiness of the children in what they are doing.''
Most of the criticism of the Suzuki method centers on two points: (1) Suzuki-trained children are not good note readers, (2) Suzuki-trained children never learn their own style because they imitate a recording.
It is true that this method gives good sound a higher priority than learning to read notes. Today, however, all Suzuki teachers teach note reading as soon as the basics of technique and listening skills are mastered.
As to the second objection, Louise Wear has a succinct comment. ''Why not imitate Perlman?''