Ken Hirai - Gaining Through Losing (Album)
Ken Hirai - Miracles (Album)
Smooth (Album)
Ken Hirai - 歌バカ 2 Ken Hirai Singles Best Collection (Compilation)
Ken Hirai - 歌バカ10th Anniversary Complete Single Collection '95 - '05 (Compilation)
Ken Hirai - 歌バカ10th Anniversary Complete Single Collection '95-'05 (Compilation)
Ken Hirai - Miracles (Single)