Aquila 6U Soprano Low G Tuning G4 (Wound) Single String. On the basis of extensive experience in the field of ancient and modern gut processing techniques, Aquila believes that only when we take inspiration from the tradition of the great string makers of the past does it become possible to discover the magic of sound that only gut, and now Nylgut, can offer. The discoveries of the past few years, including the ancient gut loading-weighting process that AQUILA first re-discovered, and the perfection of the Nylgut manufacturing process that has revolutionized the world of synthetic strings, allow us to build a bridge into the future by developing natural gut and synthetic strings with totally innovative acoustic and technological properties: the future of music has always been anticipated through strings.