When it comes to bonus tracks, most bands are content to throw together a few B-sides or remixes and call it a day.

Phoenix is not most bands. The deluxe edition of “Bankrupt!,” the French indie pop band’s fifth album and first since breakthrough LP “Wolfgang Amadeus Phoenix” hit in 2009, features no less than 71 tracks of additional material.

Many of these are under a minute long, most have untranslated French titles, and all of them are demos from the album’s lengthy recording process.

It’s an insane move, but these rough fragments reveal a lot about the album they’re packaged with. “Bankrupt!” may sound effortless and sleek on the surface, but listen a bit more closely and it becomes obvious that Phoenix put a ton of work into making it sound just right.

Interestingly enough, the band apparently expects you to put as much effort into listening to “Bankrupt!” as they put into creating it.

The LP is filled to the brim with big, glossy synth-pop, but it’s nowhere near as immediate as “Wolfgang Amadeus Phoenix” or “It’s Never Been Like That.”

Between the oddball structures of many tracks, the retro, chintzy-by-design production and lead singer Thomas Mars’ surreal, poetic lyrics, it can take several plays for these songs to “click.” Listen to the likes of “Chloroform” and “Don’t” more than a few times, though, and they’ll go from “impossible to remember” to “impossible to forget” before you can even notice.

Some tracks do stand out more quickly than others, however. Take “Trying To Be Cool,” a mid-tempo tune which could’ve been plucked straight out of the ’80s.

The chorus is great, but what really sells the song is its sleazy, vaguely-hedonistic vibe, all sickly-sweet synths and flirtatious lyrics. It’s a new look for the famously clean-cut Phoenix, but it’s one they wear surprisingly well.

Lead single “Entertainment” is another standout. The band has been using it as both the opening and closing song on recent setlists, and for good reason — it’s one of the most anthemic tracks in their entire discography.

It has a little bit of everything: a pentatonic synth hook reminiscent of “Turning Japanese,” massive, propulsive drum beats and a bridge which contains one of 2013’s greatest “whoa-oh-oh” sing-alongs thus far.

Every ’80s-influenced album needs its power ballad, and “Bourgeois” might be the best song on “Bankrupt!” because of that. Unlike most of the other songs on the disc, “Bourgeois” doesn’t try to do anything wildly unconventional in terms of structure or production.

Instead, it’s one of the few times Phoenix allows themselves to let their hair down and focus entirely on crafting epic, emotional pop. Make no mistake: This is going to be the highlight of any encore it’s played in.

Technically speaking, “Bankrupt!” isn’t Phoenix’s “difficult sophomore LP” — remember they’ve had four before this one. But given the fact that it’s the direct successor to a record that took them from cult heroes to international superstars, there’s no denying that it plays a similar role in their career.

Still, there’s a lot to love about this album once you’ve gotten properly acclimated to its ambitious nature.

Although the record’s title may seem pessimistic,  “Bankrupt!” is an album rich with ideas, energy and heart.