Outside the Mascis family home in Amherst, Massachusetts, Lou Barlow rests his head on his steering wheel, focused on a song that's forcing his small grey pick-up to shiver and shudder. He's currently hearing the latest mix of "Rude," a growler he's added to the family of 13 that he and his Dinosaur Jr. bandmates are hearing back in full for the first time since tracking for their forthcoming full-length began in early February. And as Barlow comes plodding into the kitchen through a side door moments later, he proffers some simple feedback for producer John Agnello: "More grinding" on the guitar sound. "So you'd like more attitude on the guitar then?" Agnello asks. "Nah," Barlow says. "Just more grinding. Alongside the bass."

The indie rock lifers' third still-untitled full-length since reuniting for 2006's (due tentatively via Jagjaguwar in late August) is, according to Agnello, coming together at pace. "These are three-month records, on and off," he says, of the band's post-reunion output. "And this song," he says, while cranking the volume for Marlow and drummer Murph in the skylit studio upstairs, "is so goddamned catchy you should have seen me and my 6-year-old doing a little dance to it at home."

Spiked with a layer of keys, it's a fleet-footed cousin to the vocal-less, locomotive cut guitarist J Mascis — SPIN's 5th best guitarist of all time — is listening to on repeat at a stereo downstairs, his eyes cast forward. Its "working title," Mascis purrs, is "Downtown" and it's as muscular as one might expect. For the past week, Mascis has been fighting the flu while working on guitar overdubs in isolation, pasting leads and solos to what sounds to be another remarkable addition to a catalogue that only seems to grow stronger. Today marks the first time they're all listening back together. "Shredding," Agnello bleeps, as he cues up an updated mix of "Rude" for Barlow and Murph, replete with more grinding on said solos. "Shredding. This is a shred affront."

"Perhaps best known for his role in Back To The Future, Crispin Glover has trod an independent path in acting for more than three decades.

The grunge era’s most iconic guitarist, J Mascis splits his time between his family in Berlin and the open road with Dinosaur Jr.

A renowned film buff, J Mascis leaped at the chance to take a phone call from Crispin Glover. The first time they had been introduced, the renowned actor and author quickly bonded with the grunge icon. American ex-pats dwelling in Europe, we pick up on the conversation as Mascis looks ahead to life on the road and Glover adjusts to a quiet existence in the Czech Republic."