A „Kunstkopf“ is also called a „Dummy head“. I prefer the first term.
It is a very intriguing recording device, available in the upper 4 digits EUR class if you are in need of one carved out of wood...
In modern installations, the actual head is represented by special X-aligned condenser microphones.
Before, there are wood, styrofoam & vinyl heads with inbuilt condenser microphones which allow for binaural recordings, „real stereo“, as we understand it.
Various artists, like CAN used it in their studio sessions as a recording device instead of standard microphones, since the studio seemed too sterile, too exact. With the artificial head, one could make recordings that could be perceived as if actually sitting in the natural stereo field.
Mostly, this device found a home in Radio Plays.
A very enchanting short demonstration is to be found on YT (in German):
by nokturnal