A professional public address system provides even acoustics throughout the entire room. A number of factors are responsible for this. It starts with the planning of the audio system, the selection and fine-tuning of the digital signal processors (Biamp, Bose or QSC), the amplifiers (Apart, Bittner, QSC or Yamaha), the right speakers (Apart, Bose, RCF or Yamaha) and the necessary microphones (Sennheiser or Shure). However, the proper placement of the speakers and the acoustic treatment of the walls and ceilings are also very important for future audio quality. Most digital sound processor can be freely programmed using PCs. On the one hand, this affects the technical functionality of mixing or signal routing and the settings for limiters. On the other hand, the spatial characteristics in connection with the microphones and speakers must also be considered when programming the system. There is a corresponding fine-tuning procedure for ideal balancing the system properly. With it, the understandability of speakers can be guaranteed throughout the room and proven as well.