Bill Payne is talking enthusiastically about Little Feat's sold-out gig the night before in Albany, New York.

"People say, 'Oh, it's not Little Feat without Lowell George singing and playing slide guitar, or without Richie Hayward on drums,' and they're entitled to feel that way if they want. But we still sound like Little Feat to me."

Payne should know. He's the last of the founding members still playing with this iconic rock band. George, the band's original guiding light, died in 1979 from a heart attack brought on by cocaine, alcohol and over-the-counter medicines. Their talismanic drummer, Hayward, a man who led twice as many lives as the average cat, kept powering Little Feat until shortly before his death in 2010.

Their current roll of great form, which brings them to Celtic Connections early next month, is sadly about to come to a temporary halt as singer-guitarist Paul Barrere, who joined the band in 1972, has to come off the road to receive treatment to finally rid him of the hepatitis C virus that he's been living with since 1994.

"I'm hoping that we'll be able to pick up where we leave off about a year down the line," says Payne. "I certainly feel that I've got a lot more music in me and the band feels like it has more to say. We put out our first album of new material in nine years last year, Rooster Rag, and that felt like both a new Little Feat album and in some ways like a classic Little Feat album. I can go off and do stuff with other people for a while like I've always done, but we always seem to come back to Little Feat, one way or another."

The Texas-born, California-raised Payne remembers well the meeting that led to him joining George, Hayward and original bass guitarist Roy Estrada (George's former Mother Of Invention cohort). Called to George's house in the Hollywood hills, he arrived to find a gorgeous little blonde girl playing in a living room that contained a samurai sword, a sitar (George was taking lessons from Ravi Shankar at the time), books by the Beat poets and a record collection that included comedian Lenny Bruce, jazz saxophonist John Coltrane, anarchist rockers The Fugs, some Howlin' Wolf and Muddy Waters, and a Smithsonian compilation of blues field recordings.

"I thought, this guy clearly has a broad interest in music – and eclectic interests generally – and that's how the Little Feat sound developed," he says. "We took all the ingredients that would now be known as Americana – we took our cue there from The Band, who were a big influence in showing us the importance of good songs and good musicianship without showing off – and it was really just the way we played together that created the sound. If you listen to the first two albums, they sound different to the ones that came later, but the classic Little Feat sound, the groove, had already been established."

Their first paid gig was a birthday party for songwriter Jimmy Webb, arranged for them by Fred Tackett, a songwriting friend who would join the reformed Little Feat in 1988, and although a buzz developed round them, their early albums sold only a few thousand copies each. Barrere arrived with bassist Kenny Gradney and percussionist Sam Clayton in a shake-up that produced the brilliant Dixie Chicken album (Barrere recently quipped that he arrived with a chicken and departed with a rooster, referring to the band's latest album) but major commercial success still eluded them.

"It's one of the better things that's happened, as far as making records is concerned, that these days, we don't have some record company executive saying, 'I don't hear a hit single,'" says Payne. "But while we had songs that got covered by other people and songs that you'd hear on the radio, we were never really about that kind of fame. We were more about musicianship. I remember Keith Richards came backstage at a gig in Amsterdam around 1974-75, put his arm round me and said, 'Welcome to the club.' He's one of the biggest pop stars ever but he's also a musician, he knows what goes into making good music, and that gesture meant a lot to me."

Through albums including Feats Don't Fail Me Now, The Last Record Album and one of the great live recordings of all time, Waiting For Columbus (which opens with a chant gleaned from the aforementioned Smithsonian blues compilation), Little Feat developed a large, loyal following without rivalling, say, Led Zeppelin for sales and maintained a reputation for playing live concerts of a supernatural togetherness that have passed into legend. Then George, who had expressed dissatisfaction with some of the more jazz fusion-inclined material the others were producing and was promoting his solo album, Thanks I'll Eat It Here, died. The band stalled. Payne, never short of job offers, played sessions and joined the then highly successful Bob Seger's touring band.

"About seven years after we'd laid the band to rest, we were playing in this place called The Alley in Los Angeles," says Payne. "It was where all sorts of people – Jackson Browne, Bonnie Raitt, you name 'em – used to rehearse, and we were planning to dedicate one of the rooms there to Little Feat. So we got the remaining band members together and invited some friends and we played some of the old songs, as far as we could remember them, and Christmas carols – Oh Come All Ye Faithful was one. And although we kept goofing up, I thought, 'This still sounds and feels great.' I had to go off with Bob Seger for another year's touring but I asked the guys how they felt about putting the band back on the road – and everyone said yeah."

Several replacements for Lowell George were considered. Robert Palmer, with whom the band had recorded and toured in the mid-1970s, was a possibility, as was Bonnie Raitt, although she rather inconveniently found the mass success that had previously eluded her right about the time Little Feat got back together. In the end, Fred Tackett, who had written songs with the band, and Craig Fuller from country rockers Pure Prairie League brought the band up to a seven-piece. With a few personnel shuffles – Fuller left, his replacement, Shaun Murphy came aboard until 2009 and perhaps most crucially, the band's drum tech, Gabe Ford, stepped in for the ailing Hayward – the second coming of Little Feat reached its 25th year with the arrival of 2013.

"People come out to hear us and there'll be some who really want to hear the old songs," says Payne. "That's fine because we still like the old songs too and we still learn from them. There are passages on songs on our latest album, Rooster Rag, that maybe sound a bit like Mercenary Territory from The Last Record Album or one of the other older songs, but I think that's down to having established the band's credentials and a strong identity all those years ago. I see that as drawing on experience rather than just recycling.

"Good songwriting was always a big component of what we do; rhythm was always a big component, the slide guitar was always a big component, the keyboards were always a big component, and having three or four singers – like The Band – was always important. So when you put all that together, people's impressions of who did what and when might not be as certain as they think. It almost doesn't matter who's in the band because we still make the Little Feat sound."

For Payne, who established a new writing partnership with former Grateful Dead lyricist Robert Hunter on Rooster Rag, there could be classic Little Feat songs still to come.

"I feel I'm in a really creative place in my life at the moment, and working with Robert Hunter, who has a real cinematic approach to lyrics, is great because it makes me think differently about where a song can go and how to frame each verse," he says. "We've written another seven songs in addition to the four we wrote for Rooster Rag and they could go on to my next solo album, I suppose. But they feel and sound like Little Feat songs to me."

Little Feat play 02 ABC, Glasgow on February 3 as part of Celtic Connections, www.celticconnections.com