For Yuppies, This Concert Is the Rock of the Middle Ages : Charity: Top British rockers will give a benefit performance at one of England’s stately homes before a fortysomething audience.

Rock promoter Andrew Miller boasts that a charity concert he is staging this summer has a remarkable lineup that constitutes, in his words, “the cream of British rock.”

With Paul McCartney, Phil Collins, Eric Clapton, Pink Floyd, Elton John, Cliff Richard, Mark Knopfler, Tears for Fears and Status Quo on the bill, no one can dismiss Miller’s claims as idle hyperbole.

But there is another unique aspect about the June 30 event, which takes place in a deer park in front of a stately home at Knebworth, some 30 miles north of London, and will draw possibly 120,000 people.

For perhaps the first time, a major rock event is acknowledging the fact that its audience is moneyed, enamored of comfort--and almost as advanced in years as the performers, most of them fortysomething veterans.

Knebworth has already been tagged a “yuppie concert”--and Miller doesn’t find the description unfair or unkind.

Miller figured that a fair proportion of these middle-aged rock fans would have plenty of disposable income, or even had businesses of their own. So he offered 34 executive-style hospitality suites, each holding 40 people, at a cost of $32,800 per suite.

That works out at $820 a head. For that money, the affluent concert-goers will be picked up early in the morning by a luxury bus, on which champagne is served and music videos are shown. On arrival at Knebworth, brunch will be served. The big spenders also have limited backstage access, a special viewing platform inside the park, and gourmet food available all day. The tented suites constitute what Miller dryly refers to as “the corporate village.”

“We thought the opportunity to do this was right for this event,” said Miller, who has been a concert promoter for 20 years.

His hunch paid off--within eight days, all the suites had been sold. Who bought them? “Banks, insurance companies, investment companies in the city, record companies,” says Miller.

The artists undoubtedly provide a big attraction--but so does the fact that Knebworth is a charity bash for a cause now close to the heart of the British music industry and its performers. Most of the proceeds will go to the Nordhoff-Robbins Music Therapy Center and the British Record Industry Trust school for the performing arts.

Each will collect $4.92 million, but it’s the Nordhoff-Robbins Center to which musicians feel an attachment. There, music is used to rehabilitate mentally and physically handicapped and autistic children.

All sorts of specialists in outdoor events--staging, sound, lighting and security firms--are offering their services for Knebworth at reduced rates. Music industry executives are lending their know-how to produce and market the album, video and TV sales.

At day’s end on June 30, Knebworth should have grossed about $18 million, with only about $1.6 million in costs.