Heavy metal, to use the phrase coined all the way back in the late Sixties, is among the most enduring genres of music.

Music for outsiders, often made by outsiders, metal has always skirted the mainstream, and while it's had rises and falls in popularity, it's never gone fully out of fashion. Perhaps because it's never really been in fashion in the first place. And with that, comes a lot of misconceptions.

Take Metallica, for example, pioneers of thrash. They've sold more than 120 million albums since forming in California 32 years ago, making them one of the biggest-ever bands. Despite that, the decision to book them as Glastonbury headliners this year was greeted with snorts of derision in some quarters, as if a band who regularly play to 80,000-strong crowds of their own all over the world weren't going to be able to cope with following Jack White onto the Pyramid Stage. The verdict, for most who watched their performance, seems to be that James Hetfield and co more than managed.

Another band never really given their due, despite taking their particularly British brand of metal all over the world since forming 45 years ago, are Judas Priest.

They release their 17th album - and third since singer Rob Halford rejoined in 2003 - on July 14, and it sees them back doing what they do best.

"It was a real pleasure to make," says Halford of their record Redeemer Of Souls, who's relaxing in an all-white room at the offices of Sony, the band's record label, and is in a typically good mood.

"I've had a nice breakfast and I've got a cup of tea with another on the way," he says, his West Midlands accent unsoftened, despite years living in the States. Halford lives in Phoenix, Arizona, and has houses in San Diego, Amsterdam and Walsall. "It's triple-digit weather in Phoenix at the moment," he says. "I like that heat, but they issue warnings over there when it gets below 70 degrees, so everyone remembers to take a coat out with them. They wouldn't last two minutes in the Midlands."

Naturally, Halford approved of Metallica's Glastonbury booking and hopes organisers Michael and Emily Eavis might consider booking Priest for the 2015 event.

"Metallica are our best friends," he says. "But I did have a diva moment when I heard. If people are finally going to accept metal, it should at least be British."

He cites Black Sabbath as evidence of a turning tide too. Priest's fellow Midlands rockers had their first No 1 album last year and Halford believes there's a growing need for people to hear great quality metal music.

"There's only one Black Sabbath making Sabbath music, and only one Judas Priest making Priest music. We got to No 1 on the iTunes metal chart the day we announced this album, so there's definitely an appetite for it."

It's been six years since the band's previous album, Nostradamus, was released, although stylistically, Redeemer has much more in common with their classics Sad Wings Of Destiny (1976) and British Steel (1980), the album that put them on the musical map.

"We've been very busy," says Halford. "People think when you've been away for six years you've just been sitting on your arse watching Coronation Street and eating crisps, but we never stopped. We haven't stopped since we got together actually."

Redeemer Of Souls is the band's first album made with new member Richie Faulkner. He replaced founding member KK Downing, who retired before the band's 2011 Epitaph world tour.

"We went straight into writing and recording after that tour," Halford says. "Of course, it was called Epitaph because we thought it was going to be the last thing we did, but we were in a different place then, and I think you have to get close to the end of something to realise that you don't want it to stop. We didn't want it to be a finale, so I suppose this album is our first encore."

He puts a lot of the band's second wind down to the influence of Faulkner. He's almost half the age of the rest of the band, for a start, and brought with him a whole host of new ideas and guitar-playing style.

"It's always hard when a member leaves," says Halford. "KK's influence and stamp will always be on Judas Priest, he was there from the beginning. He lives in this band, still. Having said that, there's something about Richie's excitement, charisma and power that equals what KK had.

"Richie stands on the stage and he does the business. Glenn [Tipton, guitarist] and I told him we didn't want a copycat of KK. He has his style and we wanted him to stick to that. He's his own man. Glenn and I were only saying the other day that we don't know what would've happened if we hadn't have found him."

Redeemer Of Souls, then, moves through many of the different styles Priest have touched upon over the years. There's the pure thrash of Metalizer, classic metal of March Of The Damned, and experimentation of Cold Blooded, as well as the more traditional blues of Crossfire.

"That's Richie's doing," says Halford. "He grew up a Priest fan, but started by learning the blues. Of course, metal music comes from the blues, so that song's a nod to where we come from."

Halford's particularly fond of the thunderclap that opens the album, which he says might sound cliched, but - given that Judas Priest helped shape the genre - that's allowed.

"The first line on the album is 'Welcome to my world of steel', and that's it then, we're off."

Beginning Of The End is the final song on the record, and sees Halford pay tribute to murdered serviceman Lee Rigby.

Crossfire, too, tackles the thorny issue of religious extremism, and features the lyrics, "Swearing on the bible, hypocrites and fools, losing your religion, breaking all the rules".

"We've never been afraid to dip our toe into that area," says Halford. "It's straightforward, but there other instances where I can dress up issues in other ways. You can do that in metal, like on Halls Of Valhalla," he says, referring to the album's third song.

"I've been waiting years to write something like that, I love Norse mythology and Asgard and all that. I want the song to take fans out on a longboat on the North Sea. It's just storytelling," he adds. "It goes back to the minstrels, going from village to village in the UK, singing about their adventures, or maybe writing a satirical song about the king or whatever, and I think that's what we do.

"We're metal minstrels," he adds. "Fans come to see us and they want to hear our stories. With heavy metal, you can get away with it."

EXTRA TIME - JUDAS PRIEST

:: Judas Priest formed in Birmingham in 1969, although all members apart from KK Downing had changed by the time of their 1974 debut.

:: Today, they are Rob Halford, Ian Hill, Glenn Tipton, Scott Travis and Richie Faulkner.

:: The band's named after the Bob Dylan song The Ballad Of Frankie Lee And Judas Priest.

:: British Steel is widely regarded as their biggest and best album, featuring hits Breaking The Law, Living After Midnight and United.

:: They've sold more than 50 million albums.

:: Judas Priest release their new album Redeemer Of Souls on Monday, July 14