The indie-rock outfit Firewater and the electronics duo Matmos continue their respective explorations of the world of sound on their new albums, which are out today. The New York-based Firewater, led by multi-instrumentalist and vocalist Tod A., injects a healthy dose of Eastern culture into its already exotic ramshackle rock on “The Golden Hour” (Bloodshot). And the now Baltimore-based Matmos — the constantly evolving and forward-thinking duo comprising Drew Daniel and M.C. Schmidt, who have incorporated everything from the sounds of snails crawling to the noises of surgical procedures into their sound palette — turns to nothing but synthesizers for its infectiously gleeful “Supreme Balloon” (Matador).

Tod A. — né Ashley — launched Firewater in 1995 after the demise of his inventive Cop Shoot Cop, a heavily percussive ensemble that churned out body-shaking, metallic music that sounded like some old East Coast manufacturing plant reluctantly coming to its noisy end. With Firewater, he has ventured further east, mining the rippling rhythms and song forms of Eastern European gypsy, Jewish, and folk music a good four years before Gogol Bordello blared those same influences, albeit in a punk-rock framework, out of the Lower East Side. Mr. Ashley prefers the melodic pockets for lyrical storytelling that the music tends to open up, and on “The Golden Hour,” he finds a rewarding setting for his politically exasperated ideas inside Bollywood styles and other Indian instrumentations and rhythms.

The album is informed by the ongoing American occupation of Iraq, even if Mr. Ashley never says so explicitly. Instead, he sprinkles suggestive asides abut the situation throughout: In “Borneo,” the comic complaint, “I’ve got a monkey for a president,” comes a few lines before the declaration, “I don’t want to die for the price of oil”; in “Paradise,” he sighs, “All your plans buried in desert sands / paradise comes with a price”; in “This Is My Life,” he charges, “new suit of clothes, same emperor / some people think they’re superior.”

“The Golden Hour” is, however, refreshingly void of self-righteousness, and the music is brought to ecstatic life with a rush of world rhythms. “This Is My Life” springs to life with a room-shaking funk atop a jittery explosion of Indian acoustic string instruments. The snake-charming melody of “Paradise” is formed from an intertwining web of hand percussions and stringed instruments. And “Some Kind of Kindness” is held together by a rush of male voices crying out in mass celebration.

The Eastern European vibe isn’t entirely absent here, though, especially on the album’s two standout tracks. “Weird To Be Back” slaps a dizzying version of the old “you can’t go home again” saw inside the jubilant melodies and horns of a Croatian wedding; the song even starts with what sounds like a beer can being popped open. And the lyrics for “6:45 (So This Is How It Feels)” take the form of a personal travelogue delivered in episodic snapshots, skipping around from a bar at the “end of the world” to rediscovering emptiness while “dancing on the beach.” The song’s melody is a chimera of cultures: a Brazilian tropicalia backing groove, mournful mariachi horn punctuations, a bit of dreamy Hawaiian guitar, and a ghostly Arabic violin trailing the melody. It’s a song about disappearing from the world by circumnavigating it, where music and lyrics perfectly complement each other’s anxiety.

* * *

There’s nothing anxious about “Supreme Balloon,” an instrumental album of summery, blustery good cheer. Drew Daniel and M.C. Schmidt make albums in much the same way that Lars von Trier makes movies. That is, each document is organized around some constraint or idea, be it the samples of medical procedures that shaped 2001’s “A Chance to Cut Is a Chance to Cure,” or a reliance on American and Medieval folk instruments on 2003’s “The Civil War.”

“Balloon” is formed entirely out of synthesizers, meaning nothing was recorded by microphone and processed. The synthesizers range in age from 40 years old to brand-new and include a unique “Coupigny” modular synthesizer that is housed at Paris’s famed laboratory for the style known as

musique concrète, which relies on natural environmental sounds and other nontraditional musical noises.

In many ways, what Matmos creates with “Balloon” is a form of pop

musique concrète. But don’t be misled by the album’s egghead origins. It’s one of the most instantly engaging instrumental albums you’re likely to hear. From the jaunty, almost Afro-Caribbean rhythm percolating through lead track “Rainbow Flag,” through the trancelike dream “Cloudhopper” that closes the album, “Supreme Balloon” is as light and airy as its title — and full of simple pleasures.

Even when the album gets a little thin — as during “Les Folies Françaises,” whose organ-like electronic tones recall Wendy Carlos’s space-age baroque score for Stanley Kubrick’s 1971 film “A Clockwork Orange,” anecdotally considered the first all-electronic movie score — it is produced with such sincere glee that it doesn’t feel like a mere allusion. “Balloon” is plush and bouncy, lithe and sensual, and nowhere more so than on the album’s centerpiece title song, a 24-minute opus that bubbles through a smorgasbord of squishy sounds and squiggly notes, and feels like a journey to a Roald Dahl wonderland of noises. Throughout, Messrs. Daniel and Schmidt are more interested in creating pleasurable music than in showing off gear and technique, resulting in an electronic album that’s as much fun as it is smart.