Graham Parker and Elvis Costello may not have been the angriest young men to come out of London in the late '70s, but they certainly articulated their rage with more clarity and passion than anyone else. "Angry Young Man" is not a role that can be credibly sustained for too long, though, and both singer-songwriters have spent the last two years looking for a way out of that box.

Parker, at least, has found an answer in the seasoned determination of his best album in years, "Steady Nerves" (Elektra 9 60388-1). The anger is still there, but where he once sang with a "now-or-never" desperation, Parker now digs in for the long fight. Bolstered by the support of his marriage, he turns against enemies with some confidence that he can go the distance.

Similar confidence soaks through Parker's rhythm-and-blues growl -- he sounds more like an approachable pal in the pub and less like a screamer on the corner. Parker's band, basically the same lineup as on 1983's "The Real Macaw," gives the singer his most aggressive attack since his landmark 1979 LP, "Squeezing Out Sparks."

The album's key song is "Mighty Rivers," in which Parker promises his wife to never give up fighting for love until the rivers all run dry. Parker still sees love as a struggle against all the myths and forces that distort and repress passion, but now with some hope for success. Rejecting the idea that love either falls apart or fades with time, he bellows out his stubborn faith.

Parker's new optimism is accompanied, not coincidentally, by a new melodicism in his songwriting. "Mighty Rivers" boasts a surprising chord shift in the bridge and a chorus hook that bounces upward in stuttering steps and then bursts loose. Even better is the album's most pleasurable song, "Wake Up (Next to You)," which radiates the pure romanticism of a Smokey Robinson classic. Singing atop a clever rhythm riff, Parker simmers happily in the reflective verses and bubbles over on the ecstatic choruses.

Love has in no way mellowed Parker. He launches ferocious rock 'n' roll attacks on fundamentalist missionaries in "Break Them Down," commercial TV in "Canned Laughter" and American capital punishment in "Everyone's Hand Is on the Switch."

Spurred by great playing from his longtime guitarist Brinsley Schwartz, Parker rocks harder than he has in years. He has demonstrated a way to mature without compromise or surrender; the rest of England's class of '77 would do well to emulate him.

One of this year's most impressive debut albums has been Chris Isaak's "Silvertone" (Warner Bros. 9 25156-1).

Like Parker and Costello back in '76-'77, Isaak has come out of nowhere to transform rock traditions with very personal songwriting. He claims he grew up on country music in Stockton, Calif., and didn't fall in love with rock 'n' roll until he heard the Sun rockabilly records while fighting as a boxer in Tokyo.

It hardly matters. Isaak is so talented that he gets away with posing like Elvis Presley on the album cover (reminiscent of Costello's first LP) and imitating the cinder-block echo of the early Sun discs. His dozen songs all boast hypnotic melodies behind quirky imagery, and he has a gorgeous voice.

Instead of the burning anger of the young Parker and Costello, Isaak offers the deadpan observations of Donald Fagen or Joni Mitchell. With the help of guitarist James Calvin Wilsey and an unidentified rhythm section, Isaak exaggerates the echoing vocals and twanging guitar of the Sun sessions until they take on a surreal, haunting effect. He often writes about the difficulty of breaking through an essential loneliness to connect with someone else, and his sound captures that universal feeling perfectly.

His first single, "Dancin'," grabs one's attention quickly with a perky dance riff and a brooding vocal melody. Isaak sings about the involuntary dance of love and, with a trace of desperation, asks a woman, "Why don't you help me?" Many newcomers can craft a catchy single like this, but very few can back it up with 11 others just as good, as Isaak has here. From the jungle rumble of "Voodoo" and the country romance of "Back on Your Side" to the bleak blues of "The Lonely One" and the Tex-Mex sunniness of "Pretty Girls Don't Cry," Isaak masters every idiom and turns each one into a memorable melody and a personal statement.