Just when you think you’ve seen it all.

Popular music is no stranger to what some may consider antics by a performer to make a point:

—John Lennon and Yoko Ono held two-week bed-ins to protest war.

—Radiohead allowed fans pay whatever they wanted to download the 2007 album “In Rainbows” (If you’re wondering, I don’t mind admitting I paid a whopping $0.00 for that initial download. But, I later bought it on vinyl).

—Lady Gaga wore a meat dress to promote … her unique style … ?

 

The latest is an album released exclusively as sheet music. Indie rocker Beck will release his next album, “Song Reader,” entirely as sheet music.

That’s right:

Twenty songs.

No recorded music.

No mp3s.

Only notes on paper, with a carrying case and art to go with each song.

Part of me views this as a bold experiment to make every buyer into a performer and, ultimately, a collaborator.

But to the more cynical side of me, this sounds like one musician’s way of holding up two not-so-subtle middle fingers to all the fans who’ve downloaded his music for free?

I want to give Beck the benefit of the doubt on this one.

He’s one of the more dynamic and experimenting song-writers around today, going from accidental anthem “Loser” to funky hit albums like “Odelay” to the hauntingly beautiful album “Sea Change.”

Plus, he has a track record of successful musical experiments. Beck was the driving force behind studio performances called Record Club where he, along with other musicians like MGMT and Wilco, covered classic albums like “The Velvet Underground and Nico” and “The Songs of Leonard Cohen” in one day and posted them to Youtube.

McSweeny’s, the publishing firm behind “Song Reader,” refers to the album by describing it as “an almost-forgotten form” and saying it is a medium “that enlists the listener in the tone of every track.”

It all seems so neat, hip and well-intentioned, right?

But, the organizers continue to warn, almost tauntingly, that if you want to listen to Beck’s “unfailingly exciting” songs, then “bringing them to life depends on you.”

And there lies the rub.

Two problems, Beck: I don’t play the guitar, and I haven’t read music routinely in about seven years. It’s not exactly going to be easy for someone like me to bring this album to life.

Don’t play guitar and read music? Well, you can learn or find a friend who does. Music, in the form of “Song Reader,” requires effort, and not just a few clicks of the Internet-savvy hordes.

Surely a highly-dedicated, select group (like your acoustic-guitar armed college students) is going to snarf this up, champion it and lambaste others for not knowing the best songs off this album.

But the fact is that most music listeners are lazy, and it’s difficult to expect many to go through the motions of buying and performing this album — at least very few are going to.

It seems like a move that will at best serve as a cult classic.

Don’t compare this too much to “In Rainbows” or “Record Club,” which were both based first in music. “Song Reader” appears to be a social statement/experiment first and album second.

Even if the sales are dismal, maybe it’s succeeding in its purpose by revealing something about the musical masses. Maybe it’ll show just how easy we’ve come to expect our entertainment.

Maybe it will reinstate the folk-method of sharing music almost as if by word of mouth.

Whether the result be for good or ill, I suspect it will go largely unnoticed.