"They can play anywhere, and it's especially suitable for places like Hong Kong, where homes can be quite small."

Lee believes there is still plenty of room for the instrument's popularity to grow. While the sheng has thousands of years of history and techniques informing it, which can sometimes feel alienating, the harmonica is only a few hundred years old - a familiar instrument that people can relate to.

"There hasn't been too many big changes to the harmonica in the past 100 years of its existence. The harmonicas that you find in stores today are very similar to what was available hundreds of years ago," Lee says.