Vsevolod (Seva) Yakovlevich Gakkel (Russian: Всеволод (Сева) Яковлевич Гаккель, born 19 February 1953, Leningrad USSR) — Soviet and Russian rock-musician, mostly known as cellist in "Аквариум". In 1991 founded TaMtAm music club, the first independent rock organisation in modern Russia.