The decacorde, or the 10-string guitar, is a rare variation of the classical guitar, relatively unknown even to many professional guitarists. The extra strings added to the usual 6-string instrument are no novelty but have a long history in many cultures. Thus, the evolution of this variation of the guitar shows influence from a number of different string instruments, the strongest coming from the lute family. Mari Mäntylä specializes in this rare type of guitar and has recorded an album of new compositions for the instrument.