When American musician Scott Murphy first came to Japan in 2001, he could only say a few phrases in Japanese.

“I learned how to say little things on stage, like みんな、楽しんでる？ (Minna tanoshinderu, ‘Are you guys all having a good time?’)” he says. “When you say it on stage the kids just go crazy. So I thought, the next time we come I want to be able to speak a little more Japanese.”

The singer and bassist has come a long way since. While he relocated to Japan permanently in 2014, in the last decade the Chicago native has released a number of successful albums of both covers and original music in Japanese. Known for being part of American pop punk outfit Allister and the only non-Japanese member in Japanese rock quartet Monoeyes, he is also one half of the duo Scott & Rivers, a collaboration project between himself and Rivers Cuomo, singer and guitarist of U.S. rock band Weezer.

Murphy first came to Japan while on tour with Allister. During the tour, he received a package of Japanese CDs, that included albums by artists like Spitz and Chara. They immediately sparked a life-changing interest in Japanese music.

“I went home and listened to them and just the melodies were so great,” he says. “And the sound of Japanese over the music felt so refreshing and like nothing I had heard before. The melodies were せつない (setsunai, heartrending).”

Quickly becoming engrossed in the language, he began to study it on his own during downtime on tours. After meeting and befriending the members of the band Ellegarden at the South By Southwest music festival in Austin, Texas, Allister was invited to tour Japan. Seeing an opportunity to release material in Japanese, Murphy and his band recorded the EP “Guilty Pleasures,” which featured covers of J-pop staples. The album was an unexpected success. When Allister went on hiatus, Murphy started a solo career, releasing more J-pop covers. As word spread of Murphy’s pop-punk interpretations of some of J-pop’s greatest hits, Weezer’s Rivers Cuomo came calling.

“He saw me on TV singing in Japanese. We were on the same record label, so I came into the office one day and there was a stack of Weezer CDs on the desk,” Murphy says with a laugh. “They were like, ‘Rivers Cuomo from Weezer came by and he said he wants you to check out his band.’ As if I’ve never heard Weezer!”

The duo began collaborating in 2009, and in 2012 began to play shows in Japan. Cuomo’s interest in Japan has been well-documented — most famously, his use of an ukiyo-e print for Weezer’s “Pinkerton” album cover art. His wife is also Japanese and initially helped to make sure the duo’s Japanese lyrics sounded natural to native ears.

“For this last album, she was like, ‘What you do is great, you don’t need to get my opinion any more,'” says Murphy. “So I got a lot of freedom on this album.”

Scott & Rivers released their second album, “ニマイメ” (Nimaime, literally, “second album”) in April. While containing many of the hooks and guitar rock sounds Weezer and Allister are known for, the album features a combination of distinctly Japanese lyrics and J-pop hooks.

“We weren’t trying to make it a J-pop album per se, but we were going to have to at least make it not feel out of place among other Japanese artists,” Murphy explains. “If you listen to U.S. pop, it’s the same chords over and over. Japanese pop is more about crazy chord progressions and key changes. Most U.S. pop is made for people to dance to, whereas most Japanese pop is made for people to sing karaoke to.”

Of course, the other big difference in the two pop styles is the language itself. For Scott & Rivers, the lyrics are often written in English by Cuomo, and Murphy adapts them into Japanese to fit the songs they’ve penned.

“You can’t ‘translate’ lyrics from English to Japanese,” Murphy says. “I guess that’s the correct word for it, but you really can’t just copy what you said. Because of the way the syllables work, you have to filter down when making it Japanese because English will have twice as much.”

The process often results in simple but memorable lyrics. Take, for example, the lead single “Doo Wop,” in which the song has a bridge section that goes, “誰もが持ってる 僕らの羽がある” (Dare mo ga motteru, boku ra no hane ga aru, “We have wings everyone possesses”).

“For some reason, in Japanese, you can have really simple, basic lyrics that affect in a way that they wouldn’t if written in English,” says Murphy.

Another challenge for the duo was trying to shake off the English tendency to create rhymes, which they ultimately accepted. An example can be found again in “Doo Wop,” in which the chorus goes “Doo wop, かぜのように (kaze no yō ni, like the wind). Doo wop, 今 (ima, now) sing it with me.”

“For me, one of the hardest things about writing in Japanese is telling myself that things don’t have to rhyme,” he says. “It’s hard to let that go as an American songwriter.”

As with “Doo Wop,” the songs also have moments where the lyrics switch to English, which Murphy is quick to point out is actually a J-pop trait.

“With a lot of Japanese songs, J-pop artists will use phrases in English for ふりかけ(furikake, a seasoning sprinkled mainly on cooked rice)” he says. “Rivers really wanted to do it 100 percent Japanese. When we did (the song) “カリフォルニア サンシャイン” (Kariforunia Sanshain, “California Sunshine”), he was like, ‘Are you sure I shouldn’t sing it カリフォルニア?’ I told him that because of the syllables, it wouldn’t fit the chorus as well. There are words that sound better when you sing them non-katakana-ized. I think Rivers gets it now, but at first it was a battle to get him to sing things in English, actually.”

A love letter to J-pop, “ニマイメ” is a unique album that speaks volumes about Cuomo and Murphy’s cross-cultural and bilingual experiences, and ultimately their lives.

“The first album, it was five years ago and I was living in the States. I moved to Japan three years ago to start Monoeyes. I’ve been here speaking Japanese every day. I’ve been around a lot of Japanese artists,” says Murphy. “It was easier to write this record. I think it’s because my Japanese level has gotten better.”

He smiles: “The more you do anything the better you get at it.”