by Stephen Thomas ErlewineOn Ball, Iron Butterfly began to expand their sound, attempting to write more concisely. On Metamorphosis, the group continued their musical explorations, adding a layered production to their sound. However, only keyboardist/vocalist Doug Ingle was enthusiastic about the band's new musical direction and most of the group refused to participate in the recording of the album, claiming it strayed too far from Iron Butterfly's signature sound. The truth of the matter is the rest of the band was right -- under Ingle's direction, the group tries stylistic diversions that they do not have the ability to accomplish, including funk and acoustic ballads. Nevertheless, this ambition makes for an interesting listen, since Iron Butterfly's albums can be weighed down by their relentless heaviness. Despite a handful of strong tracks -- particularly the single "Easy Rider (Let the Wind Pay the Way)" -- most of the album doesn't hold up on repeated plays.