Fans Who Miss the Past to Hear a Si of Relief : Big bands: Zentner, one of the few remaining leaders who traces his tradition to the top names of the era, will perform Sunday at Orange Coast College.

Ask bandleader-trombonist Si Zentner what happened to big bands, and here’s what he’ll tell you: “The band business didn’t die. The bandleaders died.”

The 78-year-old musician, whose orchestra plays Sunday at Orange Coast College, comes from a mold that long ago was broken. A product of the bands of Les Brown, Harry James and Jimmy Dorsey, Zentner hails from a generation in which the personality of the bandleader defined the band, and the leader was the orchestra’s main soloist.

Zentner has carried that tradition forward since forming his own big band in the mid-’50s. Though he’s long been one of the most vocal supporters of big bands, he’s currently glum about their future.

“There’s no school now for bandleaders,” he said recently in a phone conversation from his home in Las Vegas. “In those days, every bandleader came out of a band. Experience was the teacher.”

Experience is something Zentner has in spades. He was born in New York and began playing the violin at age 4. Before he was out of his teens, he won a scholarship from the Guggenheim Foundation for his trombone work.

“I was thrown out of three different schools,” he said with a laugh. “Columbia, City College of New York and Juilliard.

“I was always a classical musician,” he continued, “until one day they needed a trombone player to do a recording date with Andre Kostelanetz, and I found out what a commercial musician made as opposed to what a classical musician made.”

Zentner began working with Les Brown in 1940, moving on to the Harry James band in 1942 and the Jimmy Dorsey band the next year. “I like to say my daughter was conceived in the Harry James band and born in the Dorsey band,” he said.

It was during those early years with the great swing orchestras that he learned the craft of bandleading.

“When I was on the road, punctuality was always an important factor; the band was dressed in their traveling uniforms, they never allowed beverages on the bandstand, no one walked across the bandstand in front of the players. Little things like that become terribly important.”

Different bandleaders had different styles.

“Glenn Miller was a disciplinarian and look at the success he had,” Zentner said. “On the other hand, Harry James was very loose as a disciplinarian. But he was an impeccable musician, the best musician in the band. He had an unbelievably photographic mind when it came to music.”

Zentner moved to Los Angeles in the mid-’40s and was soon involved with the city’s busy studio scene. Between 1949 and 1955 he was on staff with MGM. “I did ‘Singing in the Rain’ and all the Judy Garland things. Those were the golden years of the musical.”

But as the studio business began to change, Zentner got the itch to stand in front of his own band. He landed a deal with Liberty Records and, in 1961, had a hit with Bob Florence’s arrangement of “Up a Lazy River.”

“Originally the company wanted me to do a Ray Conniff-type [soft-pop] album, but I told them, ‘Not me.’ I wouldn’t go along with it. I told them ‘Either it’s my way or no way.’ ”

Zentner’s orchestra went on to back such vocalists as Johnny Mathis and Nancy Wilson. But in 1968, a break in touring led him to Vegas. “They had just fired the leader of the Folies Bergere at the Tropicana, and I was offered the job, to fill in for 60 or 90 days. It ended up being four years. It was a big mistake. I sporadically put the band together, but once you take them off the road, it’s tough to get them back.”

Zentner re-formed his orchestra to play colleges and other concerts. He worked Disneyland in the late ‘80s and recently has begun traveling to Europe. But his dictum about the band--”it must be good enough to record if it travels, and good enough to travel if it records”--has been set on its ear by one record executive.

When he attempted to buy back some of his old recordings to reissue on CD, the label, which had initially agreed to the sale, refused. They were looking to reissue the recordings themselves--after Zentner dies and goes to that big ballroom in the sky.

“The guy said I was worth more to them dead than alive,” he said. “I’ve outlived most of the bandleaders. Now I’m outliving my market.”

Zentner claims he’s now playing better than ever, thanks to a certain trombone that has returned to his hands. The story of the prodigal instrument, which Zentner gave to a promising fan on a stop in Wichita, Kan., back in 1965, reflects his ongoing love for and dedication to the big-band family.

“My group opened an establishment there, and afterward I saw this young man, he must have been 6-[foot]-3, ogling me. He said he was a trombone player and asked if I would give him a lesson. So he came over the next afternoon, and he was a decent player, but he had a horrible piece of equipment. So I gave him one of mine. But then I found out that the factory quit making that trombone and couldn’t replace it. I got another trombone, but I always missed the one I gave that kid.

“Then, earlier this year, a young man came up to me in Las Vegas and asked if I remembered him. It was this kid from Wichita. He gave me back the trombone I’d given him. I’ve used it the last three dates, and it’s been a revelation. I’ve never played better in my life.”

* The Si Zentner Orchestra plays Sunday at the Robert B. Moore Theatre, Orange Coast College, 2701 Fairview Road, Costa Mesa. 4 p.m. $21 general, $15 for senior citizens and students. (714) 432-5880.