There are at least 2 bands named Larsen:

1) LARSEN were formed in 1993 in Torino, Italy. A debut album, No Arms, No legs: Identification Problems produced by Martin Bisi (Brian Eno, Sonic Youth, White Zombie, Swans...) was released in 1997. Their second album REVER was produced by Michael Gira and came out in 2002 on Gira’s Young God label. Since then they been signed to Important Records where they also maintain a collaboration with the band Xiu Xiu: Xiu Xiu Larsen.

2) The second Larsen were from Madrid and were one of the pioneers of punk rock in Spain, with a lot of influences of postpunk bands like Joy Division. Between 1980 and 1985 they made hymns like "nacido de la pota de un punk", "frontera francesa" or "lucha contra el techno". The band consisted of Monje (Jose Luis Salcines) voice, Pollo (Jose Luis Rodríguez) guitar, Rana (Ricardo Roca) bass guitar and Mosca (Gonzalo Fuentes) drums.