Soundgarden guitarist Kim Thayil is known for a lot of things—notably thick

Soundgarden guitarist Kim Thayil is known for a lot of things—notably thick guitar riffs, a graying beard, and hats. Less known, however, is his role as band archivist. Since its formation in 1984, the Seattle quartet has undertaken as many duties internally as it can. Singer Chris Cornell, for example, has grown fond of sequencing the band’s albums, arranging song orders and transitions. And Thayil has become the group’s go-to liner-note writer and keeper of old songs, a role that led him to oversee the band’s just-released 50-song holiday release, Echo of Miles (A&M Records), which comprises B-sides, non-album tracks, remixes, and more.

“Primarily all these [songs] were published, but they haven’t made an album before,” Thayil told Seattle Weekly. “Everything is compiled from a list that I maintained,” he says of the three-disc set: one disc of original material, one of covers, and one featuring instrumentals, remixes, and oddities. Thayil says he was aware of all he had to work with before sitting down to organize everything, though there were some songs he hadn’t heard in years, like the instrumental “Night Surf,” on which bassist Ben Shepherd plays all the instruments: “I hadn’t heard that since 1994, when we would play it and an accompanying film prior to taking the stage.” Both the song and the film, he says, were shelved shortly thereafter.

Thayil says he didn’t find digging through the old tracks cringeworthy. “There were things that made me cringe about 20 or 30 years ago,” he says, “but not now. Over time…those self-conscious judgments get put aside.”

Perhaps better than any of its studio releases, Echo illuminates what has made Soundgarden such an enduring act. Beyond Cornell’s muscular riffs and primal wail, the band isn’t afraid to indulge its musical whims, barreling through heavy grooves, deep psychedelia, and slick pop hooks with equal aplomb. The band also isn’t beholden to any single member’s contributions, with songwriting credits spread across all four. Soundgarden’s versatility is particularly apparent on the disc of covers, which run the gamut from the Beatles to Black Sabbath, Sly Stone to Spinal Tap.

“There are songs we do because we like [it] and some we’re doing because we like the band,” Thayil says of the covers. “Other songs we did because we thought it’d be funny if we did them. Some songs had a good groove.” Others, he says, came about just because it’s “kind of a cool song.”

Yet for all the Soundgarden history Thayil brought to light, the band’s label and management were both apprehensive about putting together Echo, since most compilations aren’t as commercially viable as studio albums. Thayil enjoyed the process nonetheless; he says he’s always enjoyed exploring the outer reaches of a band’s catalog, from Hey Jude, a collection of Beatles singles and B-sides, to Attack of the Killer B’s by Anthrax and Nirvana’s Incesticide.

After considering ideas about how to format his findings, which included paring it down to a single disc or serializing it over multiple release dates, the band settled on a three-disc set. “Casual fans that might buy a record because they heard ‘Black Hole Sun’ on the radio 15 million times, [they] may not want this,” Thayil says. “But if you love the band, you’re going to love this record. There are people who buy albums because of the strength of a single, but…I think most rock fans are not that kind of consumer. I’m thinking about the fan.”

For those fans, there’s a lot to dive into. The first disc highlights opposite ends of the band’s spectrum: “Birth Ritual” from 1992’s Singles soundtrack is anchored by a raging riff in 7/8 time that finds Cornell hitting impossibly high notes, while 2012’s “Live to Rise” from The Avengers soundtrack is a mid-tempo rocker that showcases a restrained melody and acoustic guitars. The collection also contains a number of remixes, including one from Moby (“Dusty,” from 1996’s Down on the Upside), a reverb-heavy dub version of “Big Dumb Sex,” and a frenetic seven-minute “Spoonman” from Steve Fisk.

Though a single-disc version of the collection is available at Walmart and Target, Thayil is hoping fans will opt for the complete three-disc experience, which retails for around $60 and would make an excellent holiday stocking-stuffer. What’s on his holiday wish list? “I have amps, I have guitars,” he says. “I’d like the health and well-being of everyone close to me.” Then he pauses for a moment and mentions he could use something more practical. “I need things for maintenance. Like a new furnace filter.”

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