D'Addario HS611-34M double bass string A-1 3/4, medium, nickelD'Addario HS611 34M double bass string A 1 3 4, medium, nickel Helicore Solo bass strings are tension adjusted specifically for A E B F# scordatura "solo" tuning, one whole step higher than standard tuning. They are multi stranded steel core strings that produce a warm tone quality with excellent bow response. The core design makes for strings that are very easy to play under the left hand. Damping is optimized for arco use, making them ideal for solo