Joon & Jung is an Eindhoven-based conceptual product design studio comprised of South Korean expats Joonsoo Kim and Jungyou Choi, who met while studying at a certain local Design Academy. Here's a nice in-studio making-of vid from J&J showing the construction of their Natural Speaker: Like Joey Roth, the pair have discovered porcelain's beneficent acoustic properties and have incorporated it into the design:
Whereas a lot of speakers are constructed to produce a rather fat bass and sharp high tones, we felt the sound was kind of stuck inside the speakers, missing a natural vibe and ambiance. During the development of the 'the natural speaker' we discovered the great properties of porcelain as a speaker casing, providing a clear resonance and mellow sound.
Amplified inside the ceramic and wood transmission construction, the sound gains a slight echo, creating a natural feeling of resonance, resembling the distinct flair of an acoustic instrument right in front of you.