Meet Dharni. He's a beatboxer from Singapore who is gaining international recognition for his beatboxing. He recently was featured on BeatBox Battle TV. Dharni began beatboxing in 2002 and eventually he created a buzz about beatboxing in Singapore busking on the streets when the art was relatively unheard of back then. Later Dharni founded the Singporean beatboxing community and helped pushed for the very first beatbox champonship in Singapore during the Black Eye Peas concert in 2005.
Here's a two-part clip of Dharni doing his beatbox set at the 2008 Beatbox Battle Convention in Berlin, Germany. In the first clip he does both the erhu at 3:20 and the guzheng at 4:20. Dharni even does that vibrato sound with the guzheng too. The guzheng is spot on!