Entertainment

I. Introduction
Based on the principle of fully meeting the functional requirements of the KTV entertainment room project, through careful consideration and analysis during the design process, a suitable audio system solution for the KTV entertainment room project has been found and formed. The sound reinforcement system design of the KTV entertainment room mainly ensures that its sound field has sufficient sound pressure level, good speech articulation, uniform sound field, and wideband reduction characteristics to adapt to more diverse usage functions. Especially, the wideband reduction characteristics mainly depend on the selection of the speaker brand.

II. Design Concepts
The design thought and concept are the main line of the audio system design, which runs through the entire process of the audio system design. The contents and composition of each part of the system are closely centered around this main line. Based on the investigation of newly built KTVs, private audio-visual KTVs, and nightclub audio-visual KTVs in China, and referring to relevant domestic designs, we have determined the basic design concepts of the audio system of this KTV entertainment room as follows:

Concept 1: The core goal of the audio system design serving "sound art" is to achieve high-quality sound reproduction and restoration.
Based on the research results of human auditory physiology and psychology characteristics, how to enable everyone to obtain "natural", "real", and "beautiful" auditory artistic enjoyment is a common concern of architectural acoustics and electroacoustics researchers and designers. To solve these problems, the latest research results and technical means in the acoustic field need to be used to fully reflect the more advanced artistic enjoyment brought by modern technology to people.

Concept 2: Novel sound reinforcement concept, combined with commercial structure, creates superior and innovative sound reinforcement mode.
With the development of the commercialization model, innovation is an essential direction. To create a distinctive listening environment and sound reinforcement mode, a novel sound reinforcement concept is required.

Concept 3: The application of new technologies makes system management and control more "precise" and "simple", highlighting the "humanized" design.
With the continuous progress and development of science and technology, new technologies emerge in an endless stream. There are a wide variety of equipment for selection and configuration with different functions. Under the premise of meeting the design requirements, the work of managers and operators should be made simpler and more reliable. Therefore, adhering to the "humanized" design is our basic design concept.

Concept 4: Adopt highly recognized mainstream products in the field of domestic and international performance sound reinforcement to improve the recognition and utilization rate of the hall equipment.
Pay attention to and fully understand the highly recognized mainstream product brands in the field of domestic and international entertainment sound reinforcement in equipment selection. Through various investigation methods such as visits, exchanges, and interviews, fully grasp the actual situation of the recognition of the main equipment brands, understand the development status of the equipment manufacturers, and do a good job in the key work of equipment selection to ensure that the design concept is perfectly reflected through equipment performance and final effects.

III. Sound Field Design
The sound field design focuses on solving the following aspects:
1.Sufficient sound pressure level, expanded dynamic range, and improved sound field uniformity;
2.Improve speech clarity and intelligibility;
3.Ensure an appropriate correlation between vision and the sound localization of the original sound source and simulated sound source (sound image);
4.Overcome the difficulty of listening in a complex sound environment;
5.Improve the balance between different parts (speech, music, and instrument sounds) during the performance;
6.Change the sound quality parameters in the reproduced room;
7.Modify the human voice and instrumental sounds electronically, and generate certain noises and sounds electronically to achieve special production effects;
8.Pre-generate and preset some programs to simplify technical operations;
The issues involved in points 1-4 need to be solved through the selection of speakers, the sound reinforcement form of speakers, and the placement of speakers; the issues involved in points 5-8 need to rely on the powerful functions and excellent quality of electroacoustic equipment, as well as the operation and debugging methods of electroacoustic equipment for post-processing.

IV. Design Basis
The main references in the design of the audio system for this project are as follows:
GB3241 1/1 and 1/3 Octave Band Filters for Sound and Vibration Analysis
GB3661 Technical Conditions for Measuring Capacitive Microphones
GB3785 Electrical and Acoustic Performance and Measurement Methods of Sound Level Meters
GB3947 Acoustic Terminology
GB4959 Measurement Methods for Acoustic Characteristics of Hall Sound Reinforcement
GYJ25 Acoustic Characteristics Index of Hall Sound Reinforcement System
GB50259-96 "Code for Construction and Acceptance of Electrical Lighting Devices Installation Engineering in Electrical Installations"
GB50169-92 "Code for Construction Quality Acceptance of Grounding Devices in Electrical Installation Engineering"
GBJ 232 "Code for Construction and Acceptance of Electrical Installation Engineering"
GB 50300 "Unified Standard for Construction Quality Acceptance of Building Engineering"
GB 50303 "Code for Construction Quality Acceptance of Building Electrical Installation Engineering"
GB 50057 "Code for Lightning Protection Design of Buildings"
GB/T14549/93 Power Quality, Harmonics in Public Power Grids
GB/T126661/6/90 Cable Flame Resistance Assessment Standard
GB50217/94 Cable Design Code
GB50258/96 Cable Laying Code
Other relevant national standards on the use of electrical equipment.
To adapt to the usage functions and related requirements of the KTV entertainment room, this audio system is based on the requirements of the acoustic characteristics index of the national standard of the People's Republic of China, and comprehensively considers the usage requirements of karaoke halls and private cinemas. The acoustic characteristics index of the sound reinforcement system of this project is classified as level one and is listed as follows:
Maximum Sound Pressure Level (dB)
≥103dB (within the rated passband)
Transmission Frequency Characteristics
40~12500Hz With the average sound pressure level of 80~8000Hz as 0dB, allowing +4~-8dB, and within 80~8000Hz, allowing ≤ ±4dB
Sound Transmission Gain
The average sound pressure level of 125~4000Hz ≥ -6dB
Steady-State Sound Field Nonuniformity
100Hz ≤ 10dB 1000Hz ≤ 8dB 63000Hz ≤ 8dB
Total Noise Level (Sound Reinforcement System)
NR-35

V. Conclusion
High-fidelity system. With the development of electronic technology, the bottleneck of modern sound reinforcement system's sound quality reproduction is concentrated on the transducers. The total harmonic distortion of the speakers has become one of the key factors restricting the sound quality of the sound reinforcement system. Therefore, high-parameter speakers should be selected for sound reinforcement.
Moreover, other products in the sound reinforcement system (mixer, audio processor, peripheral insertion equipment, etc.) are all selected as professional high-quality products, and the total harmonic distortion should all be less than 0.1%. It can be foreseen that the sound reinforcement system designed according to this scheme, after reasonable debugging, will be a high-fidelity sound reinforcement system.
Sufficient sound pressure level. With the development of modern recording technology and the improvement of people's auditory appreciation level, the system is required to have sufficient dynamic margin to adapt to the undistorted reproduction of large dynamic program signals. The speakers selected in this scheme have high power and high sensitivity, and the matching power amplifier has sufficient power reserve.
Good sound field uniformity. The layout of speakers in this scheme is based on the specific location and area of the listener area. Appropriate constant-directivity speakers are selected, and the listener area is within the coverage range. The sound field uniformity is good.
Smooth transmission frequency characteristics. We select high-quality speakers with a good international reputation, without excessive points and notch points, to ensure a smooth transmission frequency characteristic of the system.
Very low system noise. The generation and introduction of system noise are mainly related to the grade of equipment and system matching. In this design, high-end products with very low background noise are used. The system adopts star grounding. Each speaker system has its own power filter circuit. All external interfaces of the system adopt transformer isolation systems. Therefore, the background noise index proposed by our company in this scheme is also achievable.
High reliability and mature technology. Especially for the power amplifier and speaker unit in the system, since high-quality brands are selected and carefully debugged, the power amplifier and the speaker unit are in the best matching state. This overall system solution, in addition to being beneficial to the high-fidelity reproduction of sound quality, another important advantage is that it greatly improves the reliability of the equipment.