Carl Christoffer Lundquist, born 1970, is a Swedish musician and producer. His own band is Brainpool where he started as a bass player and backing vocalist, but has moved to play both the bass and the guitar. Brainpool won a Swedish Grammy in 1994 (best new band). He has also produced albums by Per Gessle and Gyllene Tider and played in the backing groups of Roxette and Gessle.

He has his own studio in the rural south of Sweden, The Aerosol Grey Machine Studio (AGM) in Vallarum, Scania. The AGM is primarily an analogue studio with lots of vintage equipment and two live echo-chambers. Since its start in 1998, the AGM has hosted a vast selection of both Swedish and international artists such as Roxette, Per Gessle, Ed Harcourt, Ulf Lundell, Gyllene Tider, Thåström, Bo Sundström, Wilmer X, Christian Kjellvander, Helena Josefsson, Sandy Mouche, Peter von Poehl, Justin Winokur, Doug Wyatt, and Moneybrother.

In May 2011, Christoffer released his first ever solo album, Through the Window. The album reached #29 on the Swedish album chart. Also in May, Christoffer was the first person ever to be awarded the Sir George Martin Award at a gala event in Malmö, Sweden. The award came with SEK100,000