Pop music is a huge, absurd tent that holds within it many bullshit subgenres. Kraut rock? I guess. Slowcore? Er, Glo-fi? Go fuck yourself.

The very idea, at this point, of experimenting with pop music is almost laughable. When experimenting with pop music you'd better be careful, lest your experiment be assigned a genre.

So, to hear a band label themselves - or be labeled - experimental pop is enough to prick up some ears in the music lovers' community. To be called experimental is tantamount to a music critic throwing his hands up in surrender, as if to say, "I can't compartmentalize this band, nor shall I begin to try."

If you heard Parenthetical Girls' most recent LP, Entanglements, you might be tempted to call them orchestral pop. Listen to the band's previous album, and you'll not be so quick with your designation. Despite how loaded the word "experimental" is, this is the basic definition of experimentation: Lead singer and brainchild Zac Pennington desired to make orchestral pop, and Entanglements was his experiment.

"We generally just consider the music that we make to be pop music, because it's a pretty wide umbrella, and it allows us not to have to feel like we have to do any one sort of thing," says Pennington. "As a rule, we are generally pop music fans, so it's easier to classify it that way and not put ourselves into a corner."

Pop music, I would argue, shouldn't be quite as difficult as the music of Parenthetical Girls has a tendency to be. I realize that "difficult" is a word that lends itself well to prigs and fuddy-duddies, but I think it's a fair assessment of the rigmarole Pennington insists on leading us through with his songs.

This is not to say the songs aren't enjoyable, but they take a little work on the part of the listener. Pennington expects the listener to have a modicum of patience and trust; he really is going somewhere if you'd just give him the time to make it.

I sometimes think about how it's so hard to imagine how exciting it must have been at the dawn of pop music to listen to your favorite band's latest album. When Sgt. Pepper's Lonely Hearts Club Band came out, what must have been the reaction? Listening to it today, it's still remarkable, but we have the benefit of 40 years of popular music to inform our intake of the album. Tectonic shifts - such as Sgt. Pepper - in the very identity of popular music are basically extinct.

The most we can hope for is the gradual stretching and molding of pop music that bands such as Parenthetical Girls or Deerhoof - who will both play Olympia on July 4 - can provide us. Eventually, as we've learned from the history of popular culture, there will eventually be a collapse and a rebuilding. Until then, pop bands will continue to writhe and multiply, carrying with them subtle evolutions. It's momentum at a quantum level, but it's undeniably moving forward.

All we can do is keep experimenting.

Parenthetical Girls

With Deerhoof and AU
Sunday, July 4, 7:30 p.m., $8 OFS members, $10 general
Capitol Theater, 206 Fifth Ave., Olympia
360.754.6670