Keywords: Nanchang monitoring matrix switcher, Hefei MV64*16, Jiangxi RGB, Anhui monitoring matrix, Jiujiang video surveillance, Huangshan VGA
First, the speaker is the end equipment of the music system. It plays a decisive role in the sound quality of all the sound systems. When choosing a speaker, you should start from the following aspects: 1. The sensitivity of the sound: the loudness and effect of the sound are generally known as sound pressure level. (spl) the standard to be sure, the higher the speaker sensitivity to clarify the higher its effectiveness, and the power is obviously not as sensitive as the main, this is because each increase in power 1 times the sound pressure level only increase 3db, a single speaker sensitivity is 96db /100w, B speaker single sensitivity is 96db/200w, we distinguish between two corresponding power amplifiers to promote A, B speakers (speaker and power amplifier impedance negligence). In the extra power when their sound pressure level is separated into a speaker 116db, B speakers 113db, A speaker sound pressure level higher than the B speaker sound pressure level 3db; if the B speaker to achieve a similar speaker sound pressure level, then It is necessary to add a speaker with a sensitivity of 90db/200w. That is, the sensitivity of a 96db/100w sound, the importance of sensitivity, cost performance is also evident. The large and low-efficiency sound is being replaced by high-sensitivity and small-size high-efficiency speakers. This is the current development trend of loudspeakers and the inevitable result of technological development; if you use the B-Speaker, it will increase the number of speakers and power amplifiers. While increasing the overhead, it will also cause phase distortion and sound waves between speakers due to the simultaneous use of multiple speakers. If a speaker is used, the number of speakers and power amplifiers can be reduced accordingly, which can save costs or improve the quality of power amplifiers and speakers. The main reason is that due to the reduction of speakers and power amplifiers, no significant differences occur between the speakers. The phase distortion and sound wave annoyance have greatly improved the clarity and evenness of the sound, and it is truly "low investment and good results."
2, the speaker's frequency response flatness: In order to ensure that the speaker may reach a good frequency response and average sound level, the best choice for the choice of speaker efficiency (20hz ~ 20khz) is good, the smaller the average error is not better, preferably in Sound field uniformity within the extra power range is within +/-3db.
3, speaker distortion: The speaker distortion is as small as possible, even at full power, high sound pressure output, the total harmonic distortion of all speaker systems should also be < 5 percent.
4, the speaker's directivity and coverage angle: First of all, according to the actual needs of the sound coverage angle (important here refers to the high frequency, due to the presence of strong high-frequency directivity) to determine the speaker's directivity and angle (sound wave Beamwidth), because it is directly related to the sound field's average degree and sound range (sound projection distance). The principle of real sound range is similar to that of a flashlight. The aperture has a large range and the aperture has a small range, so the range of the speaker is related to the coverage angle. Because wide-angle treble horns (most commonly 90 degrees * 40 degrees) often exhibit sound reflections from walls and ceilings and backseats that cannot be covered in the back seat, people have developed high-y-barrel drum heights. Radiators (most commonly 60 degrees * 40 degrees) use narrower treble horns to make the sound projection interval much wider than the wide treble horn projection interval and reduce wall and ceiling reflections, resulting in overall sound quality. Clear progress.
5. Speaker Disposer: Advanced speakers that need to be equipped with electronic processing controllers must use the electronic processing controller specified by the speaker and must not be easily replaced by ordinary electronic crossovers. This is because the electronic handlers are The matched speaker is specially designed and manufactured, and the crossover frequency (filter slope of the frequency divider and the number of filter segments is changed, and the corresponding adjustment can be made according to the change of the room absorption coefficient caused by changes in the room temperature and humidity, and Time difference correction, phase correction, parametric balance, delay compensation, and compaction/clipping can be performed on each frequency band of the multi-divided speaker and the speaker can be over-voltage or over-current maintained to prevent the power amplifier or speaker from being damaged. He can use electronic principles to supplement the defects caused by the cabinet structure, so that the speakers can exert their maximum effect. AV Matrix Information, the company established the Institute of Frontier Technology in Silicon Valley, USA, and is located in the Asia-Pacific region, product technology research and development base. In Guangzhou! This is the reason why the general electronic frequency divider can't be replaced.
6, the speaker's power: speaker's power and speaker's sensitivity is proportional to the speaker's power is greater, the greater the sound pressure level, so enough to select the speaker's power due to the speaker system sound pressure level design to determine the power of the speaker Size (double the power, the sound pressure level increases 3db). In addition, because the dynamics of the speakers playing back the disco music are large, it is better to adopt the eiars-426a test standard of the Electronic Industries Association of America to weigh the power of the speakers when it is sufficient to withstand the power of the speakers. The eiars-426a test scale defines that if a speaker's nominal continuous input power is 300W, then his music input power is twice as high as the nominal continuous input power, which is 600W (that is, than the continuous input The sound pressure level at power increases by 3 dB), and the power of his peak power increases by a factor of two over the input power of the music, reaching a total of 1200 (the sound pressure level is basically increased by 3 db in the music power). Only those speakers that are strictly compliant with the eirars-426 test standard will be able to ensure that the loudspeakers will ensure safe work and reduce the chance of damaging the loudspeakers in the event of large dynamic signals. How many kinds of suitable speaker combinations for large, medium and small disco ballrooms.
7. Design of sound pressure level: Because the disco dance hall needs a higher sound pressure level (the country's first-class scale is 110db), the disco ballroom's acoustic feature level index of the sound system (only on the dance floor). Select the main speaker's sensitivity and power based on the required sound pressure level, and then confirm the subwoofer that matches the main speaker. Because when the speaker enters the working condition (after full power 20s), the voice coil and the magnet heat up, their performance has been able to drop more than 6db, so there must be a certain amount of life margin in the sound pressure design, and to avoid Large dynamic signal passing period does not appear clipping and distortion should also add more than 3db dynamic surplus.
Second, the audio control room is the core of the audio system control system which has a large number of equipment and equipment installed. The sound engineer listens to the sound of the system in the sound control room, and through the inspection window, he understands the details of the situation, and operates and controls sound equipment in a timely and correct manner. AV Matrix Information has established the Institute for Advanced Technology in the Silicon Valley in the United States. , product technology research and development base is located in Guangzhou! Make the floor sound reach the best condition.
1. The situation of the audio master room and the situation of the audio control room are as follows:
(1) Closed Control Room: The closed acoustic control room is located behind the side table or auditorium. The strengths of the backing are close to the stage, convenient for contact, and short microphone connection lines, but it is more difficult to fully watch the stage, especially the sound can not be adjusted according to the sound in the direct condensing auditorium (field). The advantage of the audio control room behind the auditorium is that it can look at all the stages and adjust the sound according to the size of the sound in the hall. The problem is far from the stage. The contact is inconvenient and difficult to see. The microphone cable is longer and the device is more troublesome.
(2) Open type control room: Open type control room is usually set up in the audience room. Instead of building a machine room, the equipment is placed directly on the cabinet and work table. The strength is that it can be adjusted at any time based on the live acoustics. Insufficiency is watched by the audience and there is no good environment at all.
2, audio control room request:
(1) The volume should be as large as possible, and the volume of the acoustic control room should be as large as possible under the premise of allowing. During the recording, the listener's room of the general requesting sound engineer has a larger volume to ensure the monitoring effect. The sound control room of the sound reinforcement system is no exception. Larger volumes should be used as far as possible. The sound control room should be used to ensure the monitoring effect. This sound controller can determine according to the monitoring situation. VGA matrix switcher information completely solves the problem. The bottleneck of the quality matrix signal quality is convenient for maintenance and expansion. The VGA matrix switcher is a professional high-definition matrix developed independently, which is flexible, reliable, and easy to maintain. . The minimum net area of ​​individual audio control rooms should be greater than 15m2, and the minimum width and height should be greater than 2.5m.
(2) The sound control room inspection window should be large enough to look out on the rostrum and more than two-thirds of the district. In the audio control room at the back of the auditorium, the inspection window should be open so that the sound in the hall can be heard directly. The sill height should be higher than the last row of ground elevations. 1. Audio and video matrix information. The company relies on its rich experience and resources accumulated in the field of video communications and control for more than ten years to form a team of professional technical and industrial talents. .7m or so, so that the audience will not block the line of sight. The observation window, the status of the mixer and the status of the rest of the equipment in the sound control room should be fair. It is better to have the sound controller sitting in the seat in front of the console to see the scene through the viewing window and the side to see all the equipment on the rack.
(3) The lighting control room shall be separated from the light control room in order to prevent the electric power from disturbing the weak electricity. In the affirmative position of the sound control room, the location of the microphone socket junction box is determined, and after the loudspeaker system is arranged to determine its position, it is possible to make an economical sound reinforcement system pipeline design based on the construction of the structure and avoiding the turmoil of the powerful electricity.
(4) In a better acoustic environment, the acoustic control room should also have a good acoustic environment to facilitate monitoring. It is better to directly hear the sound effects in the field. Flat ceilings and walls should be properly sound-absorbed.
Third, the matching between audio and video equipment at all levels is more important. If not connected properly, it will not only affect the replay consequences of the equipment, but will even damage the equipment.
1, the basic requirements for equipment connection:
(1) Matching of signal levels: When connecting audio equipment, it is necessary to pay attention to the difference between the input and output signal levels of various devices. If the level of the input signal of the fore-stage equipment is too large, non-linear distortion will occur. Otherwise, the signal-to-noise ratio of the playback system will be reduced, or even the amplifier of the next-level equipment will be moved forward. Therefore, it is necessary to pay attention to the equipment when it is connected. The levels should not differ too much. If the signal level does not appear to be suitable in practical applications, the level of the input signal must be reduced by the attenuation circuit, or the level of the input signal must be promoted by the amplification circuit. The output voltage of an ordinary moving coil speaker is a millivolt. Therefore, an amplifier circuit must be provided to amplify the signal and send it to the preamplifier circuit. For recording decks, cd players, and ld players, because the output signal level is 0.755~1v, it can be fed directly to the preamplifier.
(2) Impedance matching: In hi-fi audio equipment, for example, the output impedance of the transistor power amplifier is low impedance, and the output impedance of the tube power amplifier and other equipment is high impedance. If they do not match the impedance when connected to a speaker, VGA Matrix Supplies, a professional manufacturer of VGA Matrix, has been providing valuable VGA Matrix Switchers for years! This can cause the output power of the amplifier to be unevenly distributed or worse due to the transient characteristics of the over-damped speaker. Impedance matching connections are balanced and unbalanced. Balanced means that the two-core shielded line of the transmission signal has the same impedance to ground. The so-called unbalanced type refers to two-core shielded wires, one of which is grounded. When the equalization output is connected to the unbalanced input, matching must be performed by adding matching transformers.
2. The connection mode of the connector: In hi-fi audio equipment, the connection of the equipment is realized by various connectors. The number of commonly used connectors is the following: (1) Two-pin plug: mainly used to transmit each The signal between the equipment and the input plug as a microphone input signal. According to its diameter is divided into 2.5mm, 3.5mm, 6.5mm three.
(2) Lotus plug: It is important to use as input and output plugs between audio equipment and video equipment.
(3) XLR (xlr): important for the connection between the transmitter and the amplifier,
(4) Five-pin socket (din): It is mainly used for the connection between the cassette recorder and the amplifier. It can break the sound input and output signals into one socket.
(5) rca plug: rca plug is mainly used for transmission of video signals in equipment.
(6) f, m plug: It is mainly used for input and output of radio frequency signals in audio-visual equipment.
Specific reference:
Http://
Guangzhou Mingkong Intelligent Technology Co., Ltd. Propaganda Department July 22, 2013
First, the speaker is the end equipment of the music system. It plays a decisive role in the sound quality of all the sound systems. When choosing a speaker, you should start from the following aspects: 1. The sensitivity of the sound: the loudness and effect of the sound are generally known as sound pressure level. (spl) the standard to be sure, the higher the speaker sensitivity to clarify the higher its effectiveness, and the power is obviously not as sensitive as the main, this is because each increase in power 1 times the sound pressure level only increase 3db, a single speaker sensitivity is 96db /100w, B speaker single sensitivity is 96db/200w, we distinguish between two corresponding power amplifiers to promote A, B speakers (speaker and power amplifier impedance negligence). In the extra power when their sound pressure level is separated into a speaker 116db, B speakers 113db, A speaker sound pressure level higher than the B speaker sound pressure level 3db; if the B speaker to achieve a similar speaker sound pressure level, then It is necessary to add a speaker with a sensitivity of 90db/200w. That is, the sensitivity of a 96db/100w sound, the importance of sensitivity, cost performance is also evident. The large and low-efficiency sound is being replaced by high-sensitivity and small-size high-efficiency speakers. This is the current development trend of loudspeakers and the inevitable result of technological development; if you use the B-Speaker, it will increase the number of speakers and power amplifiers. While increasing the overhead, it will also cause phase distortion and sound waves between speakers due to the simultaneous use of multiple speakers. If a speaker is used, the number of speakers and power amplifiers can be reduced accordingly, which can save costs or improve the quality of power amplifiers and speakers. The main reason is that due to the reduction of speakers and power amplifiers, no significant differences occur between the speakers. The phase distortion and sound wave annoyance have greatly improved the clarity and evenness of the sound, and it is truly "low investment and good results."
2, the speaker's frequency response flatness: In order to ensure that the speaker may reach a good frequency response and average sound level, the best choice for the choice of speaker efficiency (20hz ~ 20khz) is good, the smaller the average error is not better, preferably in Sound field uniformity within the extra power range is within +/-3db.
3, speaker distortion: The speaker distortion is as small as possible, even at full power, high sound pressure output, the total harmonic distortion of all speaker systems should also be < 5 percent.
4, the speaker's directivity and coverage angle: First of all, according to the actual needs of the sound coverage angle (important here refers to the high frequency, due to the presence of strong high-frequency directivity) to determine the speaker's directivity and angle (sound wave Beamwidth), because it is directly related to the sound field's average degree and sound range (sound projection distance). The principle of real sound range is similar to that of a flashlight. The aperture has a large range and the aperture has a small range, so the range of the speaker is related to the coverage angle. Because wide-angle treble horns (most commonly 90 degrees * 40 degrees) often exhibit sound reflections from walls and ceilings and backseats that cannot be covered in the back seat, people have developed high-y-barrel drum heights. Radiators (most commonly 60 degrees * 40 degrees) use narrower treble horns to make the sound projection interval much wider than the wide treble horn projection interval and reduce wall and ceiling reflections, resulting in overall sound quality. Clear progress.
5. Speaker Disposer: Advanced speakers that need to be equipped with electronic processing controllers must use the electronic processing controller specified by the speaker and must not be easily replaced by ordinary electronic crossovers. This is because the electronic handlers are The matched speaker is specially designed and manufactured, and the crossover frequency (filter slope of the frequency divider and the number of filter segments is changed, and the corresponding adjustment can be made according to the change of the room absorption coefficient caused by changes in the room temperature and humidity, and Time difference correction, phase correction, parametric balance, delay compensation, and compaction/clipping can be performed on each frequency band of the multi-divided speaker and the speaker can be over-voltage or over-current maintained to prevent the power amplifier or speaker from being damaged. He can use electronic principles to supplement the defects caused by the cabinet structure, so that the speakers can exert their maximum effect. AV Matrix Information, the company established the Institute of Frontier Technology in Silicon Valley, USA, and is located in the Asia-Pacific region, product technology research and development base. In Guangzhou! This is the reason why the general electronic frequency divider can't be replaced.
6, the speaker's power: speaker's power and speaker's sensitivity is proportional to the speaker's power is greater, the greater the sound pressure level, so enough to select the speaker's power due to the speaker system sound pressure level design to determine the power of the speaker Size (double the power, the sound pressure level increases 3db). In addition, because the dynamics of the speakers playing back the disco music are large, it is better to adopt the eiars-426a test standard of the Electronic Industries Association of America to weigh the power of the speakers when it is sufficient to withstand the power of the speakers. The eiars-426a test scale defines that if a speaker's nominal continuous input power is 300W, then his music input power is twice as high as the nominal continuous input power, which is 600W (that is, than the continuous input The sound pressure level at power increases by 3 dB), and the power of his peak power increases by a factor of two over the input power of the music, reaching a total of 1200 (the sound pressure level is basically increased by 3 db in the music power). Only those speakers that are strictly compliant with the eirars-426 test standard will be able to ensure that the loudspeakers will ensure safe work and reduce the chance of damaging the loudspeakers in the event of large dynamic signals. How many kinds of suitable speaker combinations for large, medium and small disco ballrooms.
7. Design of sound pressure level: Because the disco dance hall needs a higher sound pressure level (the country's first-class scale is 110db), the disco ballroom's acoustic feature level index of the sound system (only on the dance floor). Select the main speaker's sensitivity and power based on the required sound pressure level, and then confirm the subwoofer that matches the main speaker. Because when the speaker enters the working condition (after full power 20s), the voice coil and the magnet heat up, their performance has been able to drop more than 6db, so there must be a certain amount of life margin in the sound pressure design, and to avoid Large dynamic signal passing period does not appear clipping and distortion should also add more than 3db dynamic surplus.
Second, the audio control room is the core of the audio system control system which has a large number of equipment and equipment installed. The sound engineer listens to the sound of the system in the sound control room, and through the inspection window, he understands the details of the situation, and operates and controls sound equipment in a timely and correct manner. AV Matrix Information has established the Institute for Advanced Technology in the Silicon Valley in the United States. , product technology research and development base is located in Guangzhou! Make the floor sound reach the best condition.
1. The situation of the audio master room and the situation of the audio control room are as follows:
(1) Closed Control Room: The closed acoustic control room is located behind the side table or auditorium. The strengths of the backing are close to the stage, convenient for contact, and short microphone connection lines, but it is more difficult to fully watch the stage, especially the sound can not be adjusted according to the sound in the direct condensing auditorium (field). The advantage of the audio control room behind the auditorium is that it can look at all the stages and adjust the sound according to the size of the sound in the hall. The problem is far from the stage. The contact is inconvenient and difficult to see. The microphone cable is longer and the device is more troublesome.
(2) Open type control room: Open type control room is usually set up in the audience room. Instead of building a machine room, the equipment is placed directly on the cabinet and work table. The strength is that it can be adjusted at any time based on the live acoustics. Insufficiency is watched by the audience and there is no good environment at all.
2, audio control room request:
(1) The volume should be as large as possible, and the volume of the acoustic control room should be as large as possible under the premise of allowing. During the recording, the listener's room of the general requesting sound engineer has a larger volume to ensure the monitoring effect. The sound control room of the sound reinforcement system is no exception. Larger volumes should be used as far as possible. The sound control room should be used to ensure the monitoring effect. This sound controller can determine according to the monitoring situation. VGA matrix switcher information completely solves the problem. The bottleneck of the quality matrix signal quality is convenient for maintenance and expansion. The VGA matrix switcher is a professional high-definition matrix developed independently, which is flexible, reliable, and easy to maintain. . The minimum net area of ​​individual audio control rooms should be greater than 15m2, and the minimum width and height should be greater than 2.5m.
(2) The sound control room inspection window should be large enough to look out on the rostrum and more than two-thirds of the district. In the audio control room at the back of the auditorium, the inspection window should be open so that the sound in the hall can be heard directly. The sill height should be higher than the last row of ground elevations. 1. Audio and video matrix information. The company relies on its rich experience and resources accumulated in the field of video communications and control for more than ten years to form a team of professional technical and industrial talents. .7m or so, so that the audience will not block the line of sight. The observation window, the status of the mixer and the status of the rest of the equipment in the sound control room should be fair. It is better to have the sound controller sitting in the seat in front of the console to see the scene through the viewing window and the side to see all the equipment on the rack.
(3) The lighting control room shall be separated from the light control room in order to prevent the electric power from disturbing the weak electricity. In the affirmative position of the sound control room, the location of the microphone socket junction box is determined, and after the loudspeaker system is arranged to determine its position, it is possible to make an economical sound reinforcement system pipeline design based on the construction of the structure and avoiding the turmoil of the powerful electricity.
(4) In a better acoustic environment, the acoustic control room should also have a good acoustic environment to facilitate monitoring. It is better to directly hear the sound effects in the field. Flat ceilings and walls should be properly sound-absorbed.
Third, the matching between audio and video equipment at all levels is more important. If not connected properly, it will not only affect the replay consequences of the equipment, but will even damage the equipment.
1, the basic requirements for equipment connection:
(1) Matching of signal levels: When connecting audio equipment, it is necessary to pay attention to the difference between the input and output signal levels of various devices. If the level of the input signal of the fore-stage equipment is too large, non-linear distortion will occur. Otherwise, the signal-to-noise ratio of the playback system will be reduced, or even the amplifier of the next-level equipment will be moved forward. Therefore, it is necessary to pay attention to the equipment when it is connected. The levels should not differ too much. If the signal level does not appear to be suitable in practical applications, the level of the input signal must be reduced by the attenuation circuit, or the level of the input signal must be promoted by the amplification circuit. The output voltage of an ordinary moving coil speaker is a millivolt. Therefore, an amplifier circuit must be provided to amplify the signal and send it to the preamplifier circuit. For recording decks, cd players, and ld players, because the output signal level is 0.755~1v, it can be fed directly to the preamplifier.
(2) Impedance matching: In hi-fi audio equipment, for example, the output impedance of the transistor power amplifier is low impedance, and the output impedance of the tube power amplifier and other equipment is high impedance. If they do not match the impedance when connected to a speaker, VGA Matrix Supplies, a professional manufacturer of VGA Matrix, has been providing valuable VGA Matrix Switchers for years! This can cause the output power of the amplifier to be unevenly distributed or worse due to the transient characteristics of the over-damped speaker. Impedance matching connections are balanced and unbalanced. Balanced means that the two-core shielded line of the transmission signal has the same impedance to ground. The so-called unbalanced type refers to two-core shielded wires, one of which is grounded. When the equalization output is connected to the unbalanced input, matching must be performed by adding matching transformers.
2. The connection mode of the connector: In hi-fi audio equipment, the connection of the equipment is realized by various connectors. The number of commonly used connectors is the following: (1) Two-pin plug: mainly used to transmit each The signal between the equipment and the input plug as a microphone input signal. According to its diameter is divided into 2.5mm, 3.5mm, 6.5mm three.
(2) Lotus plug: It is important to use as input and output plugs between audio equipment and video equipment.
(3) XLR (xlr): important for the connection between the transmitter and the amplifier,
(4) Five-pin socket (din): It is mainly used for the connection between the cassette recorder and the amplifier. It can break the sound input and output signals into one socket.
(5) rca plug: rca plug is mainly used for transmission of video signals in equipment.
(6) f, m plug: It is mainly used for input and output of radio frequency signals in audio-visual equipment.
Specific reference:
Http://
Guangzhou Mingkong Intelligent Technology Co., Ltd. Propaganda Department July 22, 2013
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