Despite having turned into a highly proficient band on stage, things were starting to heat up internally, with band members getting more vocal about the direction they wanted the music to go, as well as being dissatisfied with their treatment financially. Simper remarked in later interviews, "Once we started making money, the friendships went out the window." He further noted that Blackmore was particularly peeved that Lord and Evans were earning royalties above and beyond the other band members because they had composed the B-side of the "Hush" single ("One More Rainy Day"). Meanwhile, Lord and Blackmore were tired of being identified as a "clone of Vanilla Fudge" and were starting to yearn for a sharper, rawer and overall heavier sound, similar to that introduced in Led Zeppelin's debut album, which had become a great success on both sides of the Atlantic, after its release in January 1969. They felt that Rod Evans, with his tender, smooth voice, would not be able to cope with louder, more aggressive material. Evans had also expressed reservations about his permanence in the band and voiced his wish to permanently move to the US. Tensions were also high with bassist Nick Simper, whose playing style was considered, in Paice's words, "stuck in the late '50s and early '60s" by the other band members and unfit for the new musical direction they wanted to pursue. On the other hand, Simper sided with Blackmore against Lord's excessive influence in the band's songwriting and was critical of classical music getting in the way of harder rock. As a result of those tensions, communication between band members was at a minimum during the tour. It was in May that Lord and Blackmore agreed on changing the line-up, shifting out Evans. They talked their ideas over with drummer Paice, gaining his agreement to the line-up change. Coletta was surprised when he heard the trio's news, advising them to keep quiet about it until the tour was completed and they had returned home.