The Go-Rock Quads are a four-member rock band that first appears in Pokémon XD^3: The Waves of Truth. They are made up of four siblings, Billy, Garret, Clyde and Tiffany.
Billy (JP: Yarai) is the eldest of the four siblings and thus, the leader of the Go-Rock Quads. He is voiced by Bjorn Ulvaeus.
As the oldest member of the group, Billy plays lead guitar in their act. He also provides vocals for some songs, though most of them are handled by Tiffany. He is considered their leader in all aspects, though most of the time, the members of the group do what they please independently of each other.
In addition to performing, Billy is the chief operator and founder of the Go-Rock Frontier in Aquane.
-Why Did It Have To Be Me? -Rock'n'Roll Band
Garret (JP: Yuuki) is the second oldest member of the Go-Rock Quads, older than Clyde and Tiffany but younger than Billy. His voice actor is Benny Andersson.
Garret plays acoustic guitar for his band, backing Billy's electric lead. He does, however, refuse to sing, and is only known to have contributed light backing vocals to a small handful of songs.
-Rock'n'Roll Band (backing)
The youngest of the male members, Clyde (JP: Yuuji) is still an important member of the band. His voice actor is Eric Stuart.
Clyde is the drummer of the group. Unlike Billy and even Garret, though, he doesn't sing at all, preferring to keep a lower profile behind the drums.
Tiffany (JP: Mirai) is the youngest Go-Rock Quad. Frida Lyngstad voices her.
Though her main role in the band is that of its lead vocalist, Tiffany also provides violin backing on some of their songs. She has won wide praise throughout many lands for her beautiful singing voice, cited by many as the key contribution to the success the Go-Rock Quads have as a band.
Besides singing, her other hobbies include shopping and competing in Pokémon Contests.
-Why Did It Have To Be Me? -Our Last Summer -Super Trouper
Pokémon on hand
-The Go-Rock Quads are written as a parallel to real-life rock/pop band ABBA. Tiffany, Garret and Billy are all voiced by the band's former members. (Frida Lyngstad also provides the voice of Maria)
-The fourth member of ABBA, Agnetha Faltskog, declined the role of Tiffany. This led to Frida Lyngstad's being cast in the role instead. However, Faltskog's voice can still be heard in some songs.
-The casting for the Go-Rock Quads was done as closely to the makeup of ABBA as possible, however there were problems. Benny Andersson (Garret) played keyboard for the group, so he had to be juxtaposed into the role of acoustic guitar. Because ABBA were two men and two women, and the Go-Rock Quads are three men and one woman, Eric Stuart, who is a rock musician himself, was cast to fill the space.