“Mountain Battles,” The Breeders’ new release, is both familiar and fresh in a way only The Breeders can be. But from a band nearly 20 years old that has released only four albums, what else would one expect?

You might remember The Breeders from their well-deserved but brief stint of fame following the single “Cannonball.” Chances are you have this song on your iTunes, and chances are you don’t remember why you have it there. At least, that’s always my experience when I come across the song, and it’s always followed by that funny “Oh yeah!” of nostalgic revelation. That’s because The Breeders, like a Dickensian ghost of the alt-rock past, have a knack for disappearing and then resurfacing just when they’re needed — just when the public is in danger of forgetting what made alternative music so great in the first place.

This applies more than ever to “Mountain Battles,” their newest album. And even if the new songs don’t rock quite like “Cannonball” did, the album’s low-key approach seems all the more appropriate given the current popularity of the fist-pumping and the experimental. The toned-down energy levels are certainly part of the album’s sincere and unassuming appeal, like an alt-rock security blanket in a time of frenzy and distress.

The best embodiment of this slightly sedated tone is the track “Walk It Off.” A modern-day take on a more classic alternative style, the track sounds like an old Pixies song put through a sort of musical coffee filter. All the ingredients of an alt-rock cruncher are present — the sporadic guitar flourishes, the gritty bass thump, the assertive, somewhat strained vocals — but now these elements, instead of overlapping and competing, are more clearly delineated and given space to breathe. The more spacious instrumentation allows lead singer Kim Deal (a former Pixies member, in fact) to guide the song herself while exploring gentler vocals. These vocals are a star feature of the album and demonstrate immense growth from her previous work. There is still a sense of frustrated alternative angst, but now it benefits from what appears to be a healthy dose of optimism. Rocking out doesn’t always have to be fist-pumping, her now-consoling voice suggests.

Many of the album’s other songs continue in this style. Tracks such as “No Way” and “It’s the Love” come to mind, for example, as they hold down the guitar-centric alt-rock fort. Here it’s all about the power chords, and just the occasional outburst of awesome. It’s the type of music that comes out of that garage down the street. You know, the garage filled with those really amazing and experienced musicians? That one.

The album’s organic, laid-back feel, however, is also largely due to the music’s incredibly varied style. After one of those aformentioned do-it-yourself jams, the band will turn around and blow you away with the melancholic, Santo-and-Johnny-inspired “Regalame Esta Noche.” The switch in musical style is almost as confusing as the switch from English to Spanish. At the same time, the way The Breeders move naturally from genre to genre seems entirely characteristic of a general attitude toward music. Starting an album with a Jane’s Addiction-type intro and finishing with a cowboy ditty and a German-language demonstration may, indeed, seem outrageous. And even if my roommate insists that it sucks and that it is not music, under the compass of The Breeders’ sincere and personable style, the genre-bending — even the German demonstration — works, oddly enough.

While many bands seem intent on living up to a certain expectation of character or energy level, The Breeders obviously play to no expectations. They record songs when they feel like it and how they feel like it. If this means borrowing from other genres, or stripping instrumentation down to simple drumstick clapping, then so be it. Twenty years ago, they were characterized as a “Boston Girl Super Group.” If, on “Mountain Battles,” they have done away with much of what made them girl-powered, or super-powered, they still do a hell of a job.