Sunbeam phosphor bronze strings are handwound upon round cores which give a terrific result…wonderful sustain…remarkable sustain. The tone does not seem to decay as do other phosphor bronze strings, which we think of as decaying in a curve. The Sunbeam phosphor seem to sustain in a straight line, until the sound ”falls off”. The Sunbeam phosphor are also musically bright, and rich sounding. Additionally they are very flexible…more so than any other string we have played.