Yes. I think pretty much every product on the Schiit webpage shows a pic of its circuit board. A circuit begins with a schematic, which represents the electrical design of a circuit. That circuit is then transformed into "circuit traces" on one or both sides of a circuit board. That board is the physical medium that holds the components of the device. It provides a way to hold the parts together, as well as connect them electrically. It also contains mounting points, which will hold the board within a case.
Once the boards are produced, the electrical components (integrated circuits, capacitors, resistors, etc) are "stuffed" onto each board, after which the components are soldered onto the board (either on something called a "wave solder machine", or manually). The finished product is then mounted into a case, which isolates the components physically and electrically from the user, and provides whatever physical interfaces are needed (volume control, USB cable, power switch, etc).
Specialization is the key to productivity in a Capitalist society.