Bassist Xrysostomos Boukalis started his association with music with classical guitar lessons at 14. At the age of 16 he began playing the electric bass in various rock groups of Kozani, where he grew up. After studying modern music theory and improvisation in Thessaliniki, he moved to Athens and completed his electric bass and classical double bass studies.

He has collaborated with many musicians, songwriters and composers.
He is the co-leader of the B.Y.S. Trio, a Charlie Haden tribute band, along with pianist Kostas Yaxoglou and drummer Nikos Sidirokastritis.

He has also recorded with the groups Strovili, Aris Papadopoulos Quartet, Lathe Viosas, as well as with Thanasis Papakonstantinou.