(1) The power distribution of the main speaker system for sound reinforcement should be based on the determined number of combined units, and the appropriate number of units should be selected according to the undistorted power conditions of the power amplifier. For the drive of the speaker, either the front-end frequency division method or the power frequency division method can be used. In order to ensure the rationality and reliability of the speaker system in the hall, it is necessary to handle the grouping and wiring technology of power distribution accurately. In large halls, in order to provide a good sense of orientation for the speaker system, it is best to allow the audience to "see" the speaker, so that the visual and auditory directions are basically the same, because for the auditory sense, the horizontal orientation is more sensitive, while the vertical orientation is relatively slow. If an appropriate delay is inserted into the main speaker system and the Hass effect is used to move the sound image down, making the speaker playback system more aligned with the sound source, then the listening effect will be improved. There are generally different types of auxiliary speaker systems other than the main speaker system, such as using ceiling speakers for background music playback in corridors and lounges, and using combination speakers or small sound columns in small VIP meeting rooms. At this point, appropriate grouping should be made based on the power, impedance (or voltage), and quantity of the selected speakers, and necessary parallel and series processing should be carried out to connect them to the power distribution board. Based on the overall power distribution, design a switchable connection circuit with the power amplifier, and select a backup amplification system to facilitate the control and operation of the mixer in the sound reinforcement control room. In addition, it is necessary to determine the power of the return and monitoring systems.

(2) The back-to-back system and required power back-to-back system are audio systems specifically established to address the auditory issues of actors and bands on stage. During the performance, the actors and band are located behind the main soundtrack speakers, and if they cannot hear their vocal effects clearly, they cannot accurately determine the feeling of the performance. So, for the sound system of theaters and dance halls, in addition to the sound system of the main soundtrack, the listening system is also essential. In addition, when the sound system in the main sound field malfunctions, the return listening system can also be used as an emergency sound system to avoid a cold situation. In general, the power of the hearing system is taken as 20% of the main sound field power. For example, if the main sound field power is 2000W, then the power of the hearing system should be 400W. In a return to hearing system, in order to make the return to hearing loudness appropriate and effective, the power of the return to hearing amplifier should be about 1.3 times greater than the power of the return to hearing speaker. In actual use, the output power of the feedback amplifier needs to be adjusted on-site. If the power of the return hearing system is too low, it will make the return hearing system meaningless; If the power of the listening system is too high, it can lead to noise and dominance, and it is easy to cause adverse effects of acoustic feedback. Therefore, special attention should be paid to adjusting the volume and effectiveness of the listening system.