Despite their ominous moniker, Philadelphia’s the War on Drugs are less concerned with the contemporary dangers of narcotics than they are with digging out backroom obscurities at the local record shop. The group’s sophomore release, Slave Ambient, filters classic Americana through a lo-fi, psych rock lens, crafting a unique brand of retro rock.

Rugged frontman Adam Granduciel spoke with the Guardian this week to discuss the band’s recent tour and return to California, which will land them in San Diego on Oct. 21.

“Good Mexican food… great guitar shops…the reefer…awesome crowds,” Granduciel recalled as personal highlights of past SoCal tour dates — a brief, yet fitting list for the young working-class warrior.

The War on Drugs hasn’t slacked off since the departure of co-founding member and rising solo artist Kurt Vile in 2008. Slave Ambient is a bold step forward in terms of songwriting and overall cohesiveness from War on Drugs’ full-length debut Wagonwheel Blues.  

“The first one was more of a collection of songs that I had that got put onto a record,” Granduciel said. “This one I began and ended as a record.”

Plus, despite several line-up overhauls since the band’s formation in 2005, Granduciel feels confident that the current War on Drugs collective will remain recording and touring indefinitely.

While listeners and critics might be quick to parallel Slave Ambient’s rambling swagger with that of classic rock singers/songwriters like Bob Dylan or Bruce Springsteen, Granduciel is first to object. He insists that motivation comes more from the lesser-known forefathers of alternative music, such as Krautrockers Neu! and countless electronic composers of the late ’70s. These nuances certainly do reveal themselves on Slave Ambient, be it in the motorik drum rhythms (of Neu!) or the atmospheric electronics that engulf the tracks and transition between them.  

According to Granduciel, the most interesting experience on tour so far  (which included shooting the shit with the likes of Dan Bejar, Craig Finn, and A.C. Newman) was when legendary Detroit producer Christopher Koltay (Iggy Pop and MC5) unexpectedly dropped in on one of their shows.  

“He was at one of our shows playing shuffle board, and I couldn’t believe he actually showed up,” Granduciel said.  “I mean, he recorded some of the greats. We went back to his house — he has the MC5 royalties so he’s doing pretty well for himself — and he took us out to his recording studio that’s 100 yards out on Lake Eerie.  It’s a floating studio on the lake. The guy had all our records!”

It’s easy to imagine Granduciel living off the grid, too; the War on Drugs’ taste for obscurities is hardly traditional.

But, like a random structure in the midst of a Great Lake, the band’s music is one impressive puzzle.