If you're of a certain age and spent quality time listening to popular music, you know very well what a cassette is. And if so, you also know how to insert a pencil into one of the sprocket-like cassette holes and smoothly re-spool the tangled tape that invariably clogged your car stereo, jam box, or Walkman. You also probably remember how the album's lyrics were printed on the J-card in such small type that they required a CDC-quality lab microscope to read them.

Given those limitations and more, it seems almost disturbing that, for almost 20 years, cassette tapes were the primary delivery system for a fan's music collection, having outpaced vinyl records and predating the invention of the CD.

Thank God, a lot of folks probably think, that those days are gone.

Or are they?

Given their debatable sound quality, structural frailty and Liliputian design and packaging possibilities, it seems to make little sense that cassettes are actually making a bit of a comeback.

"I had an odd feeling there was going to be a run on cassettes," says Kevin Clark, who co-owns SMB Music Consignments in Groton with his wife Sue Menhart — both of whom play in the locally popular Sue Manhart Band.

Clark's observation was triggered when a guy walked into their store, which is mostly focused on instruments and sound equipment with a bit of vinyl sprinkled in, and wanted them to display hundreds of record label-manufactured cassettes he discovered after buying the contents of a storage unit that had fallen into delinquency.

"I did NOT want them," laughs Menhart. "My thought was to throw them in the dumpster. But Kevin had this feeling and was insistent. I was clearly wrong."

Hundreds of spines-up cassettes are indeed stacked in neat rows amidst the store's displays of sound mixing boards, synthesizers, PA speakers, electric and acoustic guitars, and basses. To tilt one's head and quickly scan the cassettes' variety of artists and albums is like opening a door into another era. Whomever originally owned the storage unit was an indiscriminate child of classic rock through the ages. Grouped by artist, there are extensive collections of the Grateful Dead, The Doors, The Byrds, War, Santana, Bob Dylan, the Stones, Rush, Hendrix, the Beatles, Bob Marley, Cream, Crowded House, REM and on and on for ... a long time.

Armloads of cassettes

And that's AFTER the first onslaught of buyers had already raided the stock.

"I just, you know, put it on Facebook that we had a bunch of cassettes, not really thinking much about it," Menhart says, "and, suddenly, people were coming in filling boxes and taking them out by the armload. We sold 230 cassettes in two hours."

"One guy took two rows of Black Sabbath tapes — 20 in each row — scooped them all up, and left happy," Clark says. "Another guy saw it on Facebook and drove down from Boston to buy 50 hip hop cassettes."

In fact, Clark and Menhart don't really have an explanation for this sudden sonic goldrush. "Zero. Idea," Menhart says. Theories she and Clark have discussed include that someone might use the cassettes to pirate samples; that, according to one customer, drums sound better on cassette than CDs or vinyl; that many of the cassettes feature bands or albums no longer available.

"We'll see if anyone else brings any in and how well it goes," Menhart says. "Maybe it's just a one-time, freak occurrence. It's been bizarre, but it's also pretty fun."

Rich Martin, owner of the Telegraph Records Shop in New London, hasn't experienced any "running of the bulls" moments in his cassette turnover, but, he says, "Cassettes have definitely made a return. There's even an official Cassette Store Day each year now — and that's happened the last three years or so, I think. We definitely sell some each week, both new titles and old."

Martin is alluding on one hand to the old manufactured cassettes that have been sitting in someone's garage or basement — or storage unit — and on the other to a perhaps unexpected strategy from new and younger artists: They are releasing music on cassette as well as downloads as opposed to CDs or vinyl.

"Bands can get a batch of 50 cassettes made on the cheap that look professional with cool color options and package designs," Martin says. "They throw in a download code for the songs, so there's a bit more value than just selling a card with a download code on it. And cassettes are great for bands to sell at shows to fans who like to show support buying shirts and merch."

Call it nostalgia

Nick Johns, leader of the well-regarded local rock band Marvelous Liars, says they decided to make their self-titled latest album available in cassette form as well as CD and download.

"We decided to release on tape because it was a good opportunity to hear our music on another platform," Johns says. "Call it nostalgia, but there's a certain charm on tape. The hiss, the warmth. I loved my tapes when I was a kid. You'd rewind too far back to the song you want, then fast forwarding to the middle of it accidentally — just to do it all over again." He laughs and, alluding to what Martin says, adds, "We use digital download cards in them, so you can buy a physical copy of something, but have the option to download the album in any file format you want — MP3, WAV, whatever you prefer. It's fun, and people seem to enjoy it."

Johns also says he has friends in Brooklyn who run a music label called King Pizza Records.

"They have some of the best rock bands around on their roster, and they only release on tape," he says. "They sell tons, so there's definitely a market for it."

Over at Mystic Disc in Mystic, owner Dan Curland takes a visitor to a small wall unit at the rear of the store stocked with cassettes. He pulls one out and says, "Oh, no doubt, cassettes are coming back. It's a slow boat, but it's happening. It's not a huge movement, and it won't equal the heyday. But — and this is where some people think I'm crazy — I actually like the audio aspect of cassettes. To me, they have great fidelity."

Curland says, based on his experience, that a lot of hip hop artists relish the cassette form, as per the ongoing popularity of mix tapes and their portability in clubs, shops or out of an artist's car. "And with the underground movement in hip hop, maybe other bands think it's just suddenly a cool or hip thing to do again: Put out your music on cassette. It's like a statement unto itself."

Pulling up a music distribution site on his computer, Curland points to an "Upcoming New Releases" page and, scrolling down through CDs, downloads and albums, finds listing for upcoming mass-produced cassette releases by over 200 artists including Weezer's "Black Album" and the soundtrack to the film "Bohemian Rhapsody."

Curland says cassette sales at Mystic Disc follow a seasonal pattern, and he offers a different but intriguing theory in explanation.

"I sell a LOT of cassettes in summer, and I think it's because people get out their classic cars and cruise," he says. "They're valuable cars, and the owners want to keep them all-original, so they won't remove the stock cassette decks. And they come in and buy cassettes to listen to driving around."

Martin says that music is important to people — so much so that they'll find a way to have it in their lives. "Maybe, with at least some of the cassette sales, it's as simple as someone living in a small apartment. They don't have room for or can't afford a big stereo system. But if they have a jam box and get some cassettes, they've got music."