"We could have made anything we wanted to make,
So we made Wheel of Fortune
And all the popular songs.
We made a land where crap is king
And the good don't last too long."
-- Spock's Beard, "The Good Don't Last"

Progressive-rock band Spock's Beard was one of the regulars on XM Satellite Radio's (NASDAQ:XMSR) Music Lab channel, a haven for those who like their jams served up in 20-minute slabs of odd time signatures, complex musical passages, and abstruse lyrics about dragons, UFOs, and other mystical musings.

Well, no more. Music Lab, which XM bills as the channel "for musicians only," is soon to go the way of Rick Wakeman's sequined cape. Along with three other established channels, Music Lab gets the axe to help free up some bandwidth for 10 new commercial-free music stations, two of which are already on the air. The remaining eight will bow on April 17.

Actually, Music Lab and its fellow outcasts will still be available online, but I didn't buy satellite radio to listen to my favorite station on the Internet, which is where unloved XM channels go to die. That's a shame for the up-and-coming bands for whom these channels were the best, and sometimes only, way to get their music heard on a massive scale. (I discovered at least half a dozen bands through Music Lab that I otherwise probably would have never heard.) And from a personal perspective, if I'm itching to sing along in the car to, say, "The Return of the Giant Hogweed," I can't very well bring along my computer for the ride. Yeah, maybe it's time to finally buy that MP3 player.

Anyway, here's the big problem with this move: XM already has equivalents to a lot of these new channels, and they're going to be playing popular mainstream music that you can already pick up on any terrestrial-radio station. XM is also busy stressing that it will still have the most commercial-free music stations on satellite radio. Sure, the lack of ads is nice, but the big selling point for satellite radio has been the variety it offers. Yet a good chunk of this new channel lineup suggests a move toward homogenization and mass appeal, which is one of the things that makes terrestrial radio so dull. And what's the point of continuing to boast about more ad-free music channels than competitor Sirius Satellite Radio (NASDAQ:SIRI) if the new channels don't give you anything you can't already hear for free?

XM has been quick to point out that fans of these exiled channels can find a lot of the music they like on other stations, and that some of the shows on these stations are migrating elsewhere on the XM dial. But that's not the point. The beauty of niche channels is that they're not watered down with other stuff you don't want to hear.

These changes all started after Clear ChannelCommunications (NYSE:CCU) won an arbitration ruling that allowed it to begin running commercials on the four XM music channels it controls. XM is fighting back with this new rollout, and it's notable that on its new lineup card (link opens a PDF file), XM has segregated Clear Channel's four soon-to-be ad-infested music stations into their own little box, apart from the rest of the service's commercial-free fare.

Headbangers everywhere are certainly rejoicing that their beloved Liquid Metal, which has long been banished to the Web, is being resurrected with the new rollout after a long, hard fight by its fans to bring it back. But with Music Lab and its rejected special-interest brethren going away, any move toward diversity and specialty programming is ultimately negated. What's more, this isn't the first time that XM has sacrificed some of its niche channels in favor of fare that's more friendly to the masses. Throw in the new overlapping mainstream channels, and XM starts to look and sound more like a costly way to get what you can hear without a subscription on terrestrial radio. That's no way to win over new fans.

Somewhere, a Clear Channel executive must be quietly chuckling to himself.

XM is a Motley Fool Rule Breakers recommendation. For more coverage of David Gardner's favorite companies on the cutting edge, take Rule Breakers for a free, 30-day trial run.

Fool online editor Adrian Rush thinks there may be some giant hogweeds lurking in the backyard at his new house. He doesn't own shares of any companies mentioned in this story. The Motley Fool has a disclosure policy.