Metallica is currently recording their new album, presumably at their own recording studio in Northern California, (dubbed HQ), whilst venturing out now and again to play festivals and corporate gigs. What every Metallica fan is wondering is when the new album be out and what will it sound like.

Over the last few months, various members of Metallica have given vague offerings as to how the new album is coming along. From Metallica drummer, Lars Ulrich’s confirmation that we’re “F**king in it” to bassisst Rob Trujillo’s confirmation that it will be “heavy but unique” to lead guitarist Kirk Hammett’s vague contribution.

“Nothing is etched in stone.”

So what will the new Metallica album sound like?

Going back through Metallica’s catalogue, we can see some key changes in the overall song structure and style from album to album. Metallica’s debut, Kill ’em All, was straight ahead thrash, but between Cliff Burton’s “Anesthesia” and the mid-section of “The Four Horsemen,” we saw some variances that were unique to speed metal in the early 1980’s.

With Metallica’s second offering, Ride the Lightning, the band really turned the thrash-metal scene on its head by including Fade to Black on the record. A song, which was almost a ballad, turned the tables on what was metal. Metallica’s sophomore outing also included what has become a signature for the band, the instrumental, (though Burton’s bass solo on “Kill ’em All” could be included in that category as well). “Call of Ktulu” made listeners sit back and listen to what Metallica could do, not only by blasting your ears out with hostility-filled crunch, but easing you into it with no less than original, classical guitar work.

Master of Puppets, Metallica’s third album, also included an instrumental called “Orion.” One of the seminal pieces in Metallica canon, the song — and the album itself — signified Metallica’s growth as a band, and it is still considered a high point in Metallica’s discography.

Following Cliff Burton’s tragic death in 1986, Metallica’s next LP, …And Justice For All, amplified the band’s tendency towards multi-tempo, long-form metal songs. With a song length averaging around seven and a half minutes, Metallica reinforced the notion that they couldn’t care less about radio airplay, something they weren’t receiving at all at the time anyhow.

And then came the Black Album. Metallica rethought everything with their next record. The songs became much shorter on average. The full-fledged ballad was back in force with “Nothing Else Matters.” Gone were the nine-minute, epic songs with a half-dozen tempo changes. Gone were the all-encompassing, global issue lyrics in exchange for some that were extremely personal. Was it a great album? By the majority of accounts, yes, it was. By sheer album sales, it was a monster hit that made Metallica a household name and its members multi-millionaires.

Metallica’s followups to their breakthrough, self-titled LP wandered a bit, as if the band was trying to come to grips with who they were and what they were about. Load and Re-Load tried to offer everything up at once, from the ballads to the shorter songs to the longer songs to the simple metal songs — and it all seemed to get lost in the mix though there were definite high points.

After the fallout — and the resignation of bassist Jason Newsted — following the Load and Re-Load albums, Metallica was more lost than ever. Metallica frontman James Hetfield entered rehab, the circumstances of which were chronicled in the painfully honest Some Kind of Monster documentary. The subsequent album, St. Anger, received a lackluster reaction from fans and critics alike. The songs were again shorter, though, in many critic’s eyes, they were still too long. The lyrics were honest to what Metallica was feeling personally at the time, but many considered them too whiny.

What’s a metal band to do?

Metallica decided to go back to their roots. They fired Bob Rock, their producer since the Black Album, and brought in uber-producer Rick Rubin. By most accounts, (including the band’s), Rubin did little to influence Metallica’s sound other than to tell them to look at their past discography and examine their high points.

Metallica looked back at Master of Puppets and set to work. The result was 2008’s Death Magnetic. A sincere return to form for a metal band whose career has echoed one of Death Magnetic’s popular lyrics: “You rise, you fall, you’re down and then you rise again – What don’t kill you make you more strong.”

Were there haters of Death Magnetic? There sure were. And most of them had jumped on the Metallica bandwagon when the Black Album hit it big. For the rest of us, those in our 40s and 50s that were around when Ride and Master and Justice were first released, Death Magnetic was a breath of fresh air. Metallica’s latest album was a truly great album full of rage, anger, galloping rhythm crunch, amazing solos, killer drums, steady double-pumped bass, and 97 tempo changes in each overly long song.

Heaven.

So what’s next for Metallica?

If the “first pass” version of “Lords of Summer” was any indication, Metallica is still on the same road they walked when they recorded Death Magnetic. Longer songs with a multitude of “parts” may still be the norm. When Kirk Hammett recently talked about the hundreds and hundreds of guitar riffs that Metallica had on tape to sift through while they composed songs for the new record, that’s a good thing. Metallica has always been at its height when it’s “gone against the grain.” Go ahead and record those 10-minute long songs. With the success of the Black Album, Metallica has little need for any more radio airplay. They’ve come full circle and can do what they want, just like they always have.

What do you think? How will the new Metallica album sound? Are you expecting something better than Death Magnetic? Worse? Sound off in the comments below.

[Photo by Kevin Winter/Getty Images]