Two years ago, accordions and trombones in hand, Beirut introduced the world to a new sub-sub-genre: American gypsy folk pop.

This week, the band released their second full-length album, “The Flying Club Cup” — actually their fifth release (including three EPs) in just a year and a half. But the term “band” must be applied loosely in this case, since Beirut is among the new species of “bands” that are nothing more than one guy who hires other people to tour and record, a la Dashboard Confessional, Bright Eyes, The Rocket Summer etc.

Beirut is the moniker for Zach Condon of Sante Fe, N.M. — a twenty-one-year-old troubadour who dropped out of high school at the age of 16 in order to travel around Eastern Europe.

It was there that he discovered the Balkan gypsy music that would come to define his own sound. What he has created manages to be both nostalgic and innovative at the same time.

A typical track on “The Flying Club Cup” might contain recorded public service announcements from an airport lobby, accordions, bells, bouncing trombones and arcade-like bleeps and beeps. Horns saturate the album like an omnipresent mariachi band from a dusty spaghetti western. It sounds like a traveling circus.

Condon’s voice emits a kind of drifting, melodramatic warble — imagine a mixture of Ringo Starr and Rufus Wainwright. Come to think of it, he looks a lot like Wainwright too. But there the similarities end.

Wainwright is a great pop songwriter. By contrast, most Beirut songs lack much in the way of a lyrical hook. There is no pop-style resolution at the end of each chorus. Instead, the lyrics suggest places, objects and mostly melancholy states of mind.

Ultimately, generality may be the point. These are scene songs. Listening to Beirut is a bit like watching a slideshow of Old World photographs — it’s as visual as it is sonic. Should he be writing film scores instead of albums?

Beirut’s lo-li instrumentation sets a great mood for a rainy afternoon. But there isn’t enough variety. Standout tracks include “Nantes” and “In the Mausoleum,” where jazzy styling provides a nice change of pace. The Asian-influenced string melodies on this track show Beirut at its best, but the novelty wears off by the end of the album.

Today’s pop music world suffers from a kind of bipolar mania. On one side sits the mainstream, which too often feels counterfeit and derivative. On the other side sits the irony-drenched fringes of the indie scene. Precious little music is made between those extremes.

Unfortunately, while the indie world has plenty of originality, too many indie artists, in their eagerness to flee the commercial aesthetic of the mainstream, end up fleeing pleasantness itself. Being non-commercial becomes their highest musical ambition. Merely being different, however, is not that hard. Even a talented artist can get lazy, and in the end, fall into a rut.

The question for fans of Beirut is how to sustain enthusiasm for a record that sounds very much like the one before, and the one before, and the one before.

Musical growth is vital for bands who, like Beirut, create songs that are more soundscapes than songs. Most bands use similar instrumentation from track to track — drums, bass, guitar and vocal — that’s the routine. Yet melodic and lyrical hooks typically vary dramatically. And that is what keeps the material sounding fresh.

Beirut is not like that. Most of their melodic and lyrical ideas are buried beneath beautiful and intricate layers of instrumentation. It’s a swelling accordion with a chiming bell, a mandolin and a trombone — all mixed into a fluid and pleasing sound. The effect is genuinely compelling. But without bold lyrical and melodic points to distinguish one song from the next, the songs end up sounding very much the same.

If you’ve never heard of Beirut, this album could be a real treat for you. Start by buying the single “In the Mausoleum” off iTunes. If you dig it, consider buying the whole album. If, however, you’ve been following this band for a while now, the new record may feel like too much of the same old.