POP MUSIC REVIEW : Stranglers Keep Firm Grip on Basics of Rock : The band integrates three new members and plays with enthusiasm but little of the variety of which it’s capable.

When J.J. Burnel of the Stranglers told a near-capacity crowd at the Coach House that the long-running British punk ‘n’ pop band has been caught up in “a lot of changes” lately, he was referring to personnel, not chords.

The lineup for the first Stranglers tour of the United States since 1987 featured three new players, but most of the music revolved around basic, three-chord structures that are the ABCs of rock.

The Stranglers have often explored more complex and varied branches of pop-rock since emerging as part of the British punk wave of 1977, but they kept to the meaty basics during Thursday’s 85-minute set.

During the last half-hour before encores, the five-man lineup (with Burnel and keyboards player Dave Greenfield the only original players left) seemed to be playing the same barreling garage-rock number over and over.

One wished that the Stranglers had gone for more balance and variety--something that their stylistically zigzagging catalogue easily could have allowed.

But if the Stranglers were monolithic, they were not tedious. The additions were good ones who helped the band accomplish what seemed to be its main mission after a long absence, the loss of former front man Hugh Cornwell and a somewhat slick comeback album, “Stranglers in the Night”: establish an identity as a hard-hitting and enthusiastic rock band.

The new singer, Paul Roberts, was an inexhaustible energy source. The skinny, youthful-looking rocker bounced and shimmied without pause, often flinging his blond, medium-long hair about as if he were trying to send it into permanent orbit around his cranium.

Roberts sang in a grainy, theatrical, chesty voice that recalled the likes of David Bowie and Iggy Pop--nothing remarkable, but good enough, combined with his nonstop energy, to make him a first-rate focal point who completely fulfilled the front man’s role of embodying the excitement of a band’s sound.

Drummer Tikake Tobe, shaven-headed substitute for Jet Black, an original member who is ailing, drove the band with a hard-slugging, no-frills approach.

The new guitarist, John Ellis, an old Stranglers buddy and sideman now promoted to full membership, looked like the embodiment of the working-class British bloke with his shorn head, husky yeoman’s build and doughy face.

He, too, was a no-frills player: His best contributions were his riffs rather than his workmanlike solos. Ellis was not so stolid, however, that he couldn’t join in some coltish fun during a close-to-the original cover of “96 Tears.”

That ? & the Mysterians number allowed Greenfield to pay direct tribute to the thin, rinky organ sound he used to excess during the show’s first half.

Greenfield was capable of more diverse borrowings. At points he recalled Rod Argent’s Hammond organ style from Zombies days, Ray Manzarek’s tinny electric piano sound and even Keith Emerson-style blipping and buzzing on synthesizer.

The Stranglers took a while to warm up as they mixed spooky, dark-hued songs including “Southern Mountains,” from their latest album, and the new “North Winds” with such punk-leaning oldies as “Something Better Change.”

The show took on more personality with “I Feel Like a Wog,” a 1977-vintage snipe at bigotry and conformism in which Roberts’ voice dripped sarcasm.

It led off the set’s long, concluding streak of garage-rockers. One new song in that skein, “This God Is Mine,” stole unabashedly from the Yardbirds’ garage-band classic, “For Your Love.”

To Roberts’ bemusement, the receptive crowd stuck to Coach House tradition and stayed in its seats. It takes something special to get listeners, no matter how appreciative, on their feet in San Juan’s sit-down atmosphere. The Stranglers finally ignited that spark in time for the encore.

It helped that Burnel finally got around, with wry aplomb, to introducing the band and running down the Stranglers’ recent roster changes. By taking fans into the band’s confidence, he established a connection that hadn’t been there before.

The audience responded by leaping to its feet en masse through two superb encores. Along with a couple of their most blazing garage-punk albums, “Hanging Around” and “No More Heroes,” the Stranglers let their pure-pop side emerge, with fine results, on “Always the Sun” and “Duchess.”

One couldn’t help but think that a bit more of that friendly chatter and inviting pop, placed earlier in the show, would have made it a stand-up celebration much sooner.

Despite its name, the Orange County band Factory, which opened the show, has no ties to the techno-industrial rock movement. Like the Edge, the previous band for singer Jeff Wright and bassist Gordon McGrath, Factory remains too closely tied to the sound of Sting.

The band, which also includes Scott Dibble, former National Peoples Gang keyboards player, and drummer Brad Wilson, late of Too Many Joes, used its 42-minute opening set to create a moody, swirling, nicely detailed sound that was dense but not cluttered. Violinist Eugene Gore rose above the expert ensemble with propulsive, classically informed solo flights.

But the songs tended to hinge too much on a single, oft-repeated chorus hook. The main source of musical interest was dynamic rather than melodic: an ability to surge from its basic groove, a carefully crafted mid-tempo mode, to more driving, intense rock passages.

Like Sting, Wright is quite handsome, quite sincere and sings in a pleasant, reedy tenor that’s perpetually plaintive. Unlike Sting, he came off rather blandly on stage, failing to assert himself physically or otherwise grab a listener’s attention.

Factory is a talented, disciplined band that can sing and play beautifully. But it hasn’t yet discovered a way to distance itself from its influences and find a personality and songwriting voice of its own.

Maybe it should try playing a bit of industrial rock, or some other off-the-wall approach, if only as an exercise that might help it shake free of what currently is a too-predictable, too-familiar groove.