In 1978, Hé Bǎoquán (何寶泉) from the Shanghai Conservatory of Music created the Butterfly Zheng, (dié shì zhēng, 蝶式筝). Still produced today, it has 49 strings in an amazing arrangements of fixed bridges and moveable bridges.
While far more versatile than the 21-string zheng, allowing players to pick from a wide variety of scales without retuning anything, all that versatility led to complication. A player had to relearn hand patterns and adjust their spatial memory of where different notes were found. It has yet to reach the popularity of the 21-string guzheng.
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