I’m a music snob. There, I’ve said it.

It’s not like it comes as a surprise, particularly if you’ve read me in the past. I’ve even been snobby about this kind of music specifically in columns in the past.

But it comes around again with the rise of “Rock of Ages,” which I refer to as the “Guitar Hero” musical.

How can I enjoy this movie – when I have such disdain for so much of its music?

And yet I did. I had a lot more fun watching “Rock of Ages” than I expected to; I also resented how much I enjoyed it, as a light, funny spoof of a bygone era.

Because, to my ears, the music that is celebrated in “Rock of Ages” – and “Guitar Hero” and “Rock Band,” for that matter – is exactly the kind of music I abhorred when I was a critic covering rock’n’roll back in those analog days.

Games like “Guitar Hero” – and works like “Rock of Ages” – ignore the critical pantheon and focus instead on that other test of time: mass popularity. These kinds of heavy-metal, hard rock and power ballads are exactly the sort of thing we critics railed against in the 1980s, even as Bruce Springsteen, Michael Jackson and Madonna were climbing the charts.

Yet the music itself had (and still has) its fans – and those fans apparently now run the numerous “classic rock” stations around the country. They still keep bands like Queensryche, Def Leppard, Loverboy and Iron Maiden touring, years after whatever miniscule speck of musical relevance they had was long extinguished.

This further underscores the idea that what is most successful is what is best. If it sells and is popular, it must be good.

Sorry – but that doesn’t wash. At any given time in history, what is most popular is rarely the thing that has the highest quality. Once in a while – but not that often.

Now I recognize that critics aren’t always right. Over the years, movies and music that received a critical drubbing went on to be recognized as classics (example: “The Wizard of Oz” got bad reviews and didn’t do much box office when it was first released). On the other hand, I’ve always believed that things that are classic have attained that status for a reason: because they were good enough to stand the test of time.

But what “Rock of Ages” and “Guitar Hero” do is scrub away any distinctions about quality. They celebrate the mundane, middle-of-the-road material that appeals to the lowest common denominator – and they present it context-free. In other words, at this point in the 21st century, a new generation believes this stuff is “classic rock” simply because it’s old – and because they’ve been told so, by the “classic rock” radio stations that play it.

Sorry. “Layla” is classic rock. “Darkness on the Edge of Town” is classic rock. “Smells Like Teen Spirit” is classic rock.

But “Sister Christian,” “Pour Some Sugar on Me” and “Juke Box Hero” are not classic rock. They’re just old hit songs. There’s a big difference.

Journey and Motley Crue and Def Leppard are not classic rock groups; they’re just stars of a bygone era whose actual relevance to that time was minor, compared to their popularity. We critics knew it when this music was young. But that’s been forgotten in the intervening decades.

Critics tried to hold the line against mindless metal – but it was obviously a holding action that’s turned into some sort of tontine. Unfortunately, those of us who pointed out how derivative and monotonous the songs of Motley Crue, Kiss and Judas Priest were when they were in their prime have gotten older and moved on to more adult pursuits. And new generations, thanks to “classic rock” stations and “Guitar Hero” (and now, “Rock of Ages”), have discovered this music, minus any critical sensibility or sense of context about its value.

So, like I said, I had lots of fun with the film, “Rock of Ages.” But I cringed at almost every song on the soundtrack. And I bemoan its effect on a new generation.