The current a cappella boom was sparked by the song "Hitori" (Alone), which was released in March 2001 by a Japanese all-male quintet called the Gospellers, whose members are all graduates of Waseda University. It was their first hit song in the seven years since their professional debut, and the CD single sold more than 600,000 copies in the first six months after going on sale.
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Nikimathew
Viral Marketing