Similar to the Butterfly Zheng, the W sought to offer greater versatility without changing tunings. Dr. Mei Han attributes its creation in 2000 to Pan Haixin and Pan Haiwei from Hebei province. It has one side arranged in a diatonic scale, and one side in a pentatonic scale. This makes more sense to me than the Butterfly, but time will tell its popularity. I do not yet grasp how vibrato techniques would work on this. I'm not sure how many strings it has or even how to count them... possibly 29?
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