So is Kentaro Kobayashi this guy's real name and Koyama the alias, or is Koyama his real name and Kobayashi the alias? I browsed though his albums, and from what I saw, whenever his name was in English it was "Kentaro Kobayashi," but whenever it was in Japanese it was 小山健太郎, which is Koyama. The most recently-used name in our scans is Koyama on
SEGA Rally 2006 Original Sound Track, and
GMCL's default name is Koyama (the English says "Kobayashi," but the kanji and hiragana are both "Koyama," so I think he changed one of the names at some point and forgot to change the other), so I'm more inclined to say that's the real name, but I'm really not familiar with this guy aside from the original Cyber Troopers Virtual-On OST.