So, after the strong critical success but relative commercial failure (barely 1 million discs sold) of last year's experimental, atmospheric, and somewhat dissonant disc ''Kid A,'' has the English quintet Radiohead tucked its tail between its legs and scurried back to more conventional ideas of melodic, structured ''rock 'n' roll'' with its latest effort, ''Amnesiac''?

In a word, no. The vocals of Thom Yorke are more front and center. But ''Amnesiac,'' set for release Tuesday, is a close cousin to ''Kid A.'' ''Amnesiac'' was, in fact, once intended to be the second half of a ''Kid A'' double-disc.

''We recorded a record and didn't bother releasing it,'' is how Jonny Greenwood, one of the group's three guitarists, explains it. ''We spent weeks thinking and trying different variations. [But] I think we took up enough people's time with 45 minutes or whatever [on `Kid A']. I think I read the other day that the average attention span in England is now 45 minutes, so that's about right.''

The difference for many people may be that ''Amnesiac,'' if not radically different from ''Kid A,'' is more immediately engaging, more pleasant sounding, perhaps more tuneful.

Greenwood thinks a moment. ''They're both so short, by new [CD] standards, '' he says, adding that the picks for the two albums were, among band members, rather interchangeable. If, though, ''Amnesiac,'' is perceived as a gentler companion piece, Greenwood can live with that. 

In essence, Radiohead has stepped back away from angst-pop and the triple guitar workouts of yore by Greenwood, Ed O'Brien, and Yorke. They've followed the we-follow-our-nose ethos of their friends and mentors in R.E.M. Spare and meandering, desolate, beautiful, and bleak, ''Amnesiac'' is not a return to the radio-friendly rock of ''Creep'' (their 1993 hit-from-nowhere debut single) or ''The Bends,'' their breakthrough album of 1995. 

''I think we're doing what bands have done since the '50s,'' says Greenwood, ''which is [when you begin] you just copy other people's music, get excited about certain records, and want to sound like that. You hear a record that just blows you away and you just try to reproduce that feeling.''

Then, Greenwood says, you move on.

There is a perception that the most recent working method for Radiohead - whose rhythm section remains Jonny's brother Colin on bass and Phil Selway on drums - is for Yorke to bring his ideas to thee band and have the others react. ''I think in a way it was backwards from that,'' says Greenwood. ''We work fairly blindly and at a certain point what was coming from the speakers was very exciting and just felt right. The songs were working.'' 

Thematically, Greenwood says, ''I think this record is more about confrontation and detail and getting up close to things, whereas `Kid A' was more about seeing things from a distance, all about landscapes and seeing the big picture. `Amnesiac' is a lot more of actually being in the picture, if that makes any sense.''

Radiohead's relationship to the pop mainstream has always been a little uneasy. ''Creep'' propelled the band to early success, but they learned to hate the confines that song of self-loathing created, and the repeated hit-making it demanded.

Asked his relationship to the machinery of stardom, Greenwood, begins with an ''I dunno'' followed by a long ''uhhhh,'' and settles into this: ''I try to look at it as something to enjoy and experience in a certain kind of way, but, you know, it's like, it's funny. It's terrific, isn't it? How you're in mainstream magazines, and reading about who did so-and-so's hair and all that. ... The whole celebrity kind of lifestyle. I don't know, it's terrific, but it's like a car crashing. Deafening in a way.''

The painfully introverted Yorke, at least public ly, seems to bear the brunt of the burden. ''Yeah,'' says Greenwood. ''Unfortunately, he does, yes. Well he's been in the videos, which didn't help.'' 

''Amnesiac'' boasts a massive booklet of oblique pictures and words, with no pictures of the band members and no individual credits. All of this begs the question: What kind of Radiohead are we going to see on tour? The group, which declined to tour in support of ''Kid A,'' plays Suffolk Downs on Aug. 14.

Greenwood: ''We'll rehearse everything that we've done and some songs on the [new] record. And we'll just look at each other and know that it's not sounding any good and say, `Let's not play that tonight.' That will be how the night goes, really, when we're sounding good.''

One almost hesitates to ask if Radiohead is looking forward to the tour - usual softball question that that is. ''Yeah. Madly,'' says Greenwood, seemingly without sarcasm or irony. ''We're sort of indulging ourselves by playing in nice places, and yeah, it's part of what we do. I think if we didn't play concerts then we wouldn't really be Radiohead anymore.''