Weiland's vocal and musical style proved to be versatile, evolving constantly throughout his career. At the peak of Stone Temple Pilots' success in the early to mid-1990s, Weiland displayed a deep, baritone vocal style that was initially closely compared to that of Pearl Jam singer Eddie Vedder. However, as STP continued to branch out throughout its career, so did Weiland's vocal style. The band's third album, Tiny Music... Songs from the Vatican Gift Shop, had Weiland singing in a much higher, raspier tone to complement the band's more 60's rock-influenced sound on that album. Later albums showcased Weiland's influences ranging from bossa nova on Shangri-La Dee Da to blues rock and classic rock on the band's 2010 self-titled album.  Weiland's first solo record, 1998's 12 Bar Blues, represented a huge shift in Weiland's style, as the album featured a sound "rooted in glam rock, filtered through psychedelia and trip-hop." With Velvet Revolver, Weiland's vocals ranged from his classic baritone to a rawer style to complement the band's hard rock sound. A New York Post review of Velvet Revolver's 2007 album Libertad commented that "Weiland's vocals are crisp and controlled yet passionate."  Weiland's second solo album, 2008's "Happy" in Galoshes, featured a wide variety of musical genres, such as bossa nova, country, neo-psychedelia and indie rock. Weiland's 2011 solo effort, the Christmas album The Most Wonderful Time of the Year consisted entirely of Christmas music in a crooning style similar to that of David Bowie and Frank Sinatra, as well as some reggae and bossa nova.

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