Background: Carlos Santana  audio  (born July 20, 1947) is a Mexican and American musician who first became famous in the late 1960s and early 1970s with his band, Santana, which pioneered a fusion of rock and Latin American jazz. The band's sound featured his melodic, blues-based guitar lines set against Latin and African rhythms featuring percussion instruments such as timbales and congas not generally heard in rock music. Santana continued to work in these forms over the following decades. He experienced a resurgence of popularity and critical acclaim in the late 1990s.
Context: Carlos Santana's distinctive guitar tone is produced by PRS Santana signature guitars plugged into multiple amplifiers. The amps consist of a Mesa Boogie Mark I, Dumble Overdrive Reverb and more recently a Bludotone amplifier. Santana compares the tonal qualities of each amplifier to that of a singer producing head/nasal tones, chest tones, and belly tones. A three-way amp switcher is employed on Carlos's pedal board to enable him to switch between amps. Often the unique tones of each amplifier are blended together, complementing each other producing a richer tone.  He also put the "Boogie" in Mesa Boogie. Santana is credited with coining the popular Mesa amplifier name when he tried one and exclaimed, "That little thing really Boogies!"  Specifically, Santana combines a Mesa/Boogie Mark I head running through a Boogie cabinet with Altec 417-8H (or recently JBL E120s) speakers, and a Dumble Overdrive Reverb and/or a Dumble Overdrive Special running through a Brown or Marshall 4x12 cabinet with Celestion G12M "Greenback" speakers, depending on the desired sound. Shure KSM-32 microphones are used to pick up the sound, going to the PA. Additionally, a Fender Cyber-Twin Amp is mostly used at home.  During his early career Santana used a GMT transistor amplifier stack and a silverface Fender Twin. The GMT 226A rig was used at the Woodstock concert as well as during recording Santana's debut album. During this era Santana had also begun to use the Fender Twin, which was also used on the debut and proceedingly at the recording sessions of Abraxas.
Question: What is Amplifiers?. Whats the answer?
Carlos Santana's distinctive guitar tone is produced by PRS Santana signature guitars plugged into multiple amplifiers.