FOR AN orchestra player, upward mobility has long been a matter of chairs. Like the office boy who would sweep his way up to president, musicians traditionally started in the last seat of a section and played their way up to first chair.

Under this system, as Boston Symphony bassist Lawrence Wolfe explains: "Place is part of a musician's total life work. Where one sits is a visual representation of just what he has achieved in the musical world. Older musicians have worked very hard to get those positions. I can see why they want to maintain them."

This hierarchy of seats evolved from pre-conductor days when orchestras in the early 19th Century were often led by the violinist in the front row. Gradually, that seat became the concertmaster's chair, and an entire class structure lined up behind him -- with such fine distinctions as sixth-stand, first violins and fourth-stand, second violins.

In recent years, however, a new breed of musicians has arisen to challenge the sanctity of place.

"There are those who spend their whole life worshipping a chair," says 26-year-old violinist Desi Alston, who is starting his fifth season with the National Symphony. "That's ridiculous."

Alton is a beneficiary of the fact that things are changing -- and rapidly in some cases. Because of new attitudes, more democratic in outlook, the sanctity of place is fading. So is submissiveness.

The player in today's major orchestra take for granted a 52-week contract, decent touring conditions and a base pay of about $25,000. He wants more than material reward, and is less willing to accept the back seat that tradition once dictated. Gone are the days when, as one musician recalled, the best advice was "to keep your mouth shut, play the notes in front of you, collect your check, and go home."

Nowhere is the change more evident than in the string sections of such orchestras as the Boston, Philadelphia and the National Symphony. Tracking one of their players over a season will reveal an elaborate game of musical chairs.

The technical name, for the string game is "revolving." In its most comprehensive form, as practiced by the National Symphony, all of the string players in a section -- except the first stands -- shift places and take on a new stand partner every two weeks. In its modified form, as practiced by the Boston and Philadelphia orchestras, there is a so-called "grandfather clause" making revolving voluntary for present orchestra members, but mandatory for new players. Since older players may not be inclined to give up their forward seats voluntarily, the results can sometimes seem absurd. In the Philadelphia Orchestra, for example, only the last three bass players shift; and in the Boston, only the last two.

Asked what difference it made in the sound, ninth bass Wolfe said: "None. We're doing it mainly for show. It involves two people and five feet at the most. On any given night, I can look Ozawa in the eye or out of the corner of my eye as he walks out. And that's all."

On the other hand, everybody in the National Symphony's viola section, except the first-stand principals, hops around according to a complicated scheme determined by a computer. At the start of a cycle, players draw a number to determine their place in a series of seating patterns, each of which lasts two weeks. At the end of 20 weeks, after everybody in the viola section has played with everyone else, players throw their numbers in a hat and start all over again.

The public may well wonder what's in a place, since a chair by any other name would still seem to be a chair. Place, however, can affect income. In recognition of their solo role and section responsibility, principals have always received more, as do those who share the first stand and those who sit in other forward rows.

Being far forward could also mean money in terms of outside positions, a benefit particularly important in the days before 52-week contracts. Rightly or wrongly, the general view was: The closer to the front, the better the player. Anyone looking for a teacher or booking a playing job tended, therefore, to start at the front.

Almost all string players will agree that being stuck at the back of a section can be demoralizing personally and damaging musically. "There is a loss of self-esteem at the back," said Marylou Speaker, the Boston Symphony's principal second violinist. "When you sit closer to the front everything is much more sensitive."

Another way of dealing with the frustration stemming from the demands of the literature is "rotation," which sounds like another word for revolving but is not the same. Its goal is a more systematic sharing of the work load for all players. Certain works, particularly from earlier periods, call for a reduced orchestra. In the past, the procedure was to cut from the bottom up. Typical was the case of bassist Curtis Burris, who spent six years with the Philadelphia Orchestra and never played a Mozart symphony. The Mozart orchestra normally uses only five basses, so Burris, occupying first the ninth and then the eighth position, was never included.

While some musicians might never play a Mozart symphony, others might find themselves playing all the time though receiving no more money. Bending over backwards to be fair, the Boston Symphony now assigns one credit for each five minutes of playing time under an elaborate rotation scheme that has personnel manager Bill Moyer balancing players' credit loads like a college advisor.

Benefiting most from the gradual dissolution of the old seniority system are new players who are no longer stuck in the last chair of a section, "paying their dues," as one orchestra member put it, waiting for someone to retire or die. Furthermore, once a whole string section (excepting the front stands) is continually shifting, such designations as sixth-stand viola or fifth-stand cello can no longer carry connotations of inferior ability. The Boston Symphony plans ultimately to revolve all violins (always except the front stands) in one large cycle so that with time even second violins will fade away. String players will be either principals or unranked section members.

Though almost everyone favors rotation, revolving has brought certain problems. NSO violinist William Foster favors revolving, but noted that, "It's more work because you have to be more flexible and adjust to different styles.I, for one, used to rely on putting fingerings and marks in my part. Now it's important not to put marks on a part because they may confuse other people. I have to adjust to having that stuff more in my head."

Although place within a section is crucial to a string player, it has less relevance for the rest of the orchestra where, generally speaking, one person plays one part. Musicians on instruments other than strings tend to worry more about their place in relation to the orchestra as a whole. French horn players, in particular, need to be very careful about the company they keep.

"Where I work most of the time is very bad," said NSO French horn player Daniel Carter. "I am either inside the timpani or underneath the cymbals or with the trumpets in back of my head. I have cotton in my ears occasionally to keep from going deaf."

More than personal inconvenience is involved, however. Certain cancellations of sound can take place when, for example, the sound can take place when, for example, the French horns sit in front of the trumpets, explained Carter, noting that over the last 15 years the French horns have virtually circled the stage, playing behind the violins, to the left of the stage away from the violins, center stage and somewhat to stage right.

Brass and woodwind players tend to feel the nature of their instruments leaves them no hiding place if things go wrong. "On any instrument you can have a bad night," explained Stevens, "but with the brass it doesn't have to be a bad night. It can be just one bad note and it's heard by 3,000 people at the same time. How many people notice if one out of 17 strings makes a mistake? If the conductor makes a mistake, maybe 100 people in the orchestra know and a few in the audience who are very familiar with the score."

From their place in the back, percussionists have to adjust their sound to the different pace of every other section. "The illusion of rhythm of every other section. "The illusion of rhythm is never accurate," explained the NSO's principal percussionist Anthony Ames. "The orchestra is too big, there are too many choirs, too many acoustical factors. I rarely play with anybody. I am constantly anticipating."

The best place in the orchestra is right in the middle, says Toshiko Kohno, the NSO's principal flutist, because "you're not too far away from anybody and you can see the conductor directly in front of you." Even given their ideal location, Kohno said that flutists, like most players, can still have trouble hearing themselves in a big orchestral tutti. "But that's not so important," she added "because you should feel the whole music as part of you. Your body is actually all over the stage. It's like a big tree and you're just one leaf, but you're sensitive to what happens on any of the other branches."

Though principals have a larger say, not everyone covets a first chair. "It's just the same as if you're not the first lady," said violinist Cathleen Dalschaert of the Philadelphia Orchestra. "Just because you're not the first lady doesn't mean you're nobody."

NSO violist Foster agreed: "I'd rather play in a fine orchestra as a tutti member, expressing a much greater personality than my own, than play in a mediocre orchestra as a principal."

Even principals can feel the urge to quit their chairs, according to Ralph Gomberg, the noted oboist who has been principal with the Boston Symphony for 30 years. "Basically, we have to be artistic four concerts a week. This means not only physical but also mental wear and tear. It's like telling Picasso to produce four paintings a week, regardless of how he feels. Maybe it can be done sometimes, but not continuously for 10 or 15 years."

As a cure for orchestral fatigue, Gomberg proposes sabbaticals as well as a larger pool of musicians playing more concerts but also making more rotation possible -- a common practice in larger European orchestras. Addressing these intangile areas of satisfaction and renewal is, according to Boston's personnel manager Moyer, "the challenge for this decade." In addition to revolving and rotation, orchestra members are increasingly involved in artistic and audition committees, and aided in solo and chamber music appearances.

Despite the problems, few orchestral musicians would change their jobs. What keeps them in their chairs is not much different from what brings the audience to theirs.

"We were playing the Beethoven Fifth a few weeks ago and I was so impressed by the greatness of that symphony," sighed BSO oboist Gomberg. What? Beethoven's Fifth? "Yeah, that's right. The old war horse. I've played it at least 1,000 times, if you include rehearsals. Still, there's something in it that remains so great."