The Passione range for cello comprises metal upper strings and gut lower strings. The A and D strings inspire pearly resonance and have great longevity. They demonstrate a complex overtone spectrum and have a remarkable full-bodied, warm, rich and round tone. These strings give a precise and focused sound right up to the highest register. They are oustandingly responsive and transition smoothly between A and D. Meanwhile, the Passione G and C strings have a brilliant and powerful sound with excellent projection. The lower string tension of Passione G and C strings allows the instrument to open up and the upper register can vibrate easily and freely.