About five years ago, one of those serendipitous quirks of the music business made it seem, fleetingly, as if a bunch of underground folk musicians might find their way into the mainstream.

About five years ago, one of those serendipitous quirks of the music business made it seem, fleetingly, as if a bunch of underground folk musicians might find their way into the mainstream.

The genre, you may remember, was referred to as free folk, or acid folk, or something involving the New Weird America, and a couple of its main players did make the jump, after a fashion: Devendra Banhart, the scene’s most visible activist, now a Warner Bros recording artist and Beck collaborator, if not quite the superstar some of us believed he could be; and Joanna Newsom who has, I think, made two of the best albums of the past decade.

For most of their fellow travellers, though, the media buzz barely registered as distant static. Over on the eastern side of the States, a variety of musicians, who had once worked together as Tower Recordings, seemed particularly oblivious to the fuss. Tower Recordings more or less patented the scene’s blend of rustic vibes and freewheeling experimentation in the ‘90s, and most of their former members – notably Matt ‘MV’ Valentine and Erika ‘EE’ Elder – continue to work prolifically and with a beatific disdain for most every commercial expediency.

One Tower alumnus, though, has remained largely unknown, but worked steadily at finding harmony between this loose and fractious music and a plusher, more traditionally-finished brand of classic rock. Pat Gubler has been recording as PG Six out of New York for a decade now, beginning with a couple of beautiful and mildly unnerving albums (“Parlor Tricks And Porch Favorites” and “The Well Of Memory”) steeped in the British folk tradition. 2007’s “Slightly Sorry”, however, found Gubler letting go of the autoharp and moving into electrified Canyon terrain, the material created by following the exercises in a Jimmy Webb book on songwriting.

“Slightly Sorry”’s belated follow-up, “Starry Mind”, is out any day now on Drag City, and is another fine album. Once again, the songs seem rooted in British tradition; I keep thinking of the brawny virtuosity of Fairport Convention circa “Full House” whenever I play it. This time, though, Gubler seems to be moving into heavier territory. If “Slightly Sorry” referenced Neil Young, crafted songs like “January”, “Palace” and “Talk Me Down” devolve further into some seething, mathematically-calibrated jams.

A couple of 2011’s best albums work as neat companion pieces: Arbouretum’s churning take on folk-rock, “The Gathering”; and the modal Southern Rock workouts that punctuate White Denim’s “D”. That said, Gubler is a gentle, undemonstrative singer, and there’s still a calmness and restraint to his music. On “Starry Mind”, he revisits an eldritch folk song from 2004’s “Well Of Memory”, and gives it a driving makeover, but manages to add heft without losing much in the way of fragility.

It’s a difficult trick to pull off, perhaps, but one that Gubler seems to have mastered.

For further reference, check out “Golden Trees”, the album he put out as part of Metal Mountains on the Amish label earlier this year. Metal Mountains constitutes a partial Tower Recordings reunion, with Gubler and Samara Lubelski backing up the vocals of Helen Rush. The prevailing mood is ethereal and psychedelic, a purposefully disorienting extrapolation of folk that’s reminiscent of Espers. PG Six’s career might seem to describe a slow passage towards the light, but evidently, sometimes he can’t resist heading back into the undergrowth.