This guy makes several installations of speakers.
One is inspired by a traditional Torii gate in Japan, now located in Kamayima, and is accessible to anyone with Bluetooth, low level white noise and a plug for a mic. It is quite a massive karaoke installation 
This one is in Canada, made of e-wastes and recycled speakers and is intended to be mobile for using in festivals.
1000 Loudspeakers, 20 amplifiers, assorted recycled electronic materiels, 1 answering machine + telephone number. People can call up the Ship and talk LOUD through 1000 loudspeakers for 3 minutes.
