to my ears
In the Japanese version of the games, Riku is voiced by Miyano Mamoru. In the North American version, he is voiced by David Gallagher.

Name: Miyano Mamoru
Birthdate: June 8, 1983
Hometown: Saitama, Japan
Other Notable Voice Roles: Kiba (Wolf's Rain), Tamaki (Ouran Koukou Host Club), Raito (Death Note)

Name: David Gallagher
Birthdate: February 9, 1985
Hometown: Queens, New York City
Other Notable Voice Roles: Seiji (Mimi wo Sumaseba)

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