Corelli cantiga strings for violin and viola are made from a new core created from a new polymer, which is totally different from nylon. It offers unprecedent characteristics.- A new intense, rich, focus and clean sound with large harmonic spectrum- A very lively and responsive string allowing the finest nuances- A very easy response in all positions.-Newly designed machines, the specific construction and material of CANTIGA strings contributes to their great longevity with perfect stability of their tonal charcteristics (tuning, harmonics...)The string settles-in very quickly; immediatly making a difference while the first notes are played, and improving again in few hours.Perfect balance between the four strings (tone and projection). All the musicians who participated to the test decided to keep the full set.Very important: Cantiga strings fit modern and antique instruments perfectly.