Evan Grant is the founder of seeper, a London arts and technology collective. This talk, recorded at TEDGlobal in Oxford in 2009 and posted to YouTube that September, is a quick tour of cymatics as both science and art: plates, water, and the idea that a sound can be read off a surface as a pattern.
The pitch is enthusiastic, and some of it is speculative. The talk suggests cymatics could help analyse complex sounds such as dolphin calls; that is a hypothesis rather than an established method, and it has not become one in the years since. The strongest parts are the simplest: the demonstration that pattern complexity rises with frequency, and the case that visualisation is a legitimate way to think about sound.
At six minutes it is a reasonable first stop for a newcomer, provided they take the applications section as an invitation rather than a result.