For devotees of classical music in Boston, there’s more bad news: HMV’s flagship Harvard Square store will close on May 10, another victim of the skyrocketing commercial rents that have changed the make-up of the Square over the past 10 to 15 years. Fans of pop music and jazz will still have both Tower Records and Newbury Comics nearby. But in the wake of the demise of the Massachusetts Avenue Tower, the Harvard Square HMV was the one place in town where you could still find a decent segment of classical music’s deep catalogue. " This is the biggest classical selection in the area, " says Fred Harrington, a sales associate and buyer in the classical department. " We carry a lot of imports and things that other stores don’t. "

Heading up Boston’s surviving classical outlets is the Virgin Megastore that replaced Tower on Mass Ave, but it’s no match for its predecessor. The Tower store that appeared briefly on Boylston Street has also closed; the small one in Harvard Square has seen its classical department shrink. The classical selection at Newbury Comics is negligible, as it is at HMV’s Downtown Crossing outlet.

Given that the classical recording industry is in the doldrums and that the standard repertoire has been re-recorded to death, skeptics will doubtless ask whether we really need a store that offers 20 different recordings of Beethoven’s Ninth. The answer depends on how seriously you want to listen to the music. It’s a standard truth about a great work (and even some not-so-great works) that every performance says something different, and that knowing a work means knowing its performance history. Especially for works that exist in alternate versions — Bach’s St. John Passion, the Mozart Requiem, most of the Bruckner symphonies — a variety of recordings becomes a necessity, and one that’s often not filled by what the major labels are currently offering.

Apart from soaring rents and the industry downturn, the HMV Harvard Square store has suffered from the huge increase in on-line shopping over the past few years. It’s true that discounts and free shipping often come with buying over the Web. But what’s good for the goose isn’t always good for the gander. Amazon.com supplies a minimum of information: composer, title, performers, record label. And it’s not the same as being able to walk into a store and dig through what’s there.

Neither is there any substitute for an experienced staff — just ask anyone who patronized Sam Goody’s in New York in the 1950s. Hearing from a knowledgeable salesperson how a new recording of Beethoven’s Fifth stacks up against Klemperer and Kleiber is worth a lot more than the often ridiculous customer reviews so popular on-line. And an on-line store’s " customers who bought this also bought that " referrals are more often inane than informative. If you’re interested in complete recordings of the Mozart piano concertos, does it help when Amazon tells you that customers who bought Géza Anda’s classic cycle also bought Norah Jones’s Come Away with Me?

But this is about more than high rents or who recorded the best version of Mahler’s Sixth Symphony. Boston prides itself on its classical-music culture, and indeed the number of music schools and concerts here would be the envy of any American city outside New York. But that culture needs more than public/private funding and box-office receipts; it needs good places to buy recordings and scores. Over the past decade, both Franklin Music and Briggs and Briggs have closed, leaving Yesterday Service (which now operates out of Cambridge Music) as the city’s only real source of study scores (Boston Music continues to stock a small selection). The closing of Newbury Street Tower and now the Harvard Square HMV reminds us that the health of classical music’s supporting institutions is in increasing peril.