A sound reinforcement system for a rock concert in a stadium may be very complex, including hundreds of microphones, complex live sound mixing and signal processing systems, tens of thousands of watts of amplifier power, and multiple loudspeaker arrays, all overseen by a team of audio engineers and technicians. On the other hand, a sound reinforcement system can be as simple as a small public address (PA) system, consisting of, for example, a single microphone connected to a 100 watt amplified loudspeaker for a singer-guitarist playing in a small coffeehouse. In both cases, these systems "reinforce" sound to make it louder or distribute it to a wider audience.