In the early ’90s, American string-music explorers Henry Kaiser and David Lindley released a series of albums focused on music from the island of Madagascar. Perhaps the most stunning of the Malagasy musicians they "discovered" was a previously unknown acoustic-guitarist from the south of the island named D’Gary. He had the finger-style chops of a Leo Kottke or a Michael Hedges and an entrancing vocabulary of moody tunings and fleet rhythms, all of which are very much in evidence on his new Akata Meso (Indigo), his sixth album and his best yet. On July 16 D’Gary made his first appearance at Harvard Square’s House of Blues, mesmerizing a crowd who’d shown up for the equally impressive headliner, Rokia Traoré of Mali.

The son of a gendarme, D’Gary was born in 1961 in a Bara village but grew up in the coastal city of Tulear. "The popular music in Tulear was blues, pop music, mixed with traditional music," he told me in Madagascar last year. "You would find groups that played dances with one guitar, bass, and drums." It was only when his father died, in 1978, that D’Gary returned to his birth village, and as traditional musicians from throughout the region gathered for the funeral observances, he got a powerful introduction to the roots music that was all around him. "It was the first time that I had seen people playing the Malagasy violin, the valiha [a tubular harp], the accordion, a cappella singing, and traditional dancing. When someone dies, the Bara musicians who sing are like people crying — it’s the same melody."

D’Gary continued to play pop music in a traveling band. But, moved by his revelation at the funeral, he began to develop a more personal approach to the guitar, one inspired by Malagasy traditions. "People didn’t know me, because I hid everything away. Each time we made a tour around different parts of Madagascar, I took advantage of the time alone in my room to work. I tried to do all these things that were sounding in my head. Even when I was walking around, I was hearing flute melodies, kabosy [traditional mandolin] melodies, accordion, a cappella singing. These made me find the open tunings. But nobody found me. If somebody came, I wouldn’t play, because it wasn’t yet ready. My thing is not easy."

That’s an understatement. D’Gary’s approach is intensely technical, full of rapid arpeggios, glissandos, prickly muted passages, and dramatic stop-and-start melodies. It’s also haunted by an agitated melancholy that can be traced back to his father’s funeral. Akata Meso ("Green Grass") both summarizes and extends his achievements as a guitarist. There’s lots of fingerpicking filigree, and it’s often lashed to fast 12/8 rhythms, as on "Lamba Flanelle" and "Plaisir-nao Mbatro." Four of the 12 tracks are exquisite instrumentals; among the vocal numbers, "Zaza Somondrara," and "Resaka Marandray" use distinctive Malagasy choral harmony. The new elements include some driving percussion played on West African djembe drums and Indian tabla. On two tracks, D’Gary plays electric guitar, and he absolutely rocks — just listen to "Bobo-drano," with its racing, roaring guitar étouffé (muted guitar) and its driven tabla accompaniment.

When asked to explain his music, D’Gary resorts to personal mythology. He calls his style "Gofo," a conflation of French and Malagasy that to him means "government of the heart." "There is no need to find a minister of culture here," he told me with a chuckle. "That’s Gofo. Freedom. Every time I play the guitar, there are lots of open strings. That’s freedom. That’s Gofo. Sometimes I play very fast things. That’s freedom. That’s Gofo."

Even as he’s been largely overlooked by Madagascar’s unimaginative pop-music industry, D’Gary has become a hero of traditional musicians there. He noted with pleasure that players of the very traditional instruments that once inspired him now routinely play their own versions of his compositions. And his appearance on American stages is bound to prove a revelation, especially for guitar freaks. He currently performs with just two accompanists, who play brisk hand percussion and surround his soulful voice, by turns a silky whisper and a ragged growl, with beautiful harmonies. At the House of Blues, in a set that mostly featured newer material, he could be overwhelming — his playing was so packed with dizzying rhythms that it left the crowd breathless at times. But there were also moments of serenity and lyricism, especially in the harmonized vocal melodies, and that contributed to the balance of beauty and bombast that’s come to embody D’Gary’s "Gofo" style.