Heavy was
Iron Butterfly's debut album, released in early 1968. Most of the songs are fairly simple and based largely on the opening riffs, interspersed with some pop songs and blues covers.The first two tracks, "Possession" and "Unconscious Power", were both written by keyboardist
Doug Ingle and released as the respective sides of a single."Iron Butterfly Theme" is a riff-driven instrumental, and one of the longest tracks on the album (it is over four minutes long). It contains some musical themes also present in the band's mega-hit "
In-A-Gadda-Da-Vida".
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