Tag Archives: Car Amplifier

5, power lines, control lines and signal lines to connect
This is a serious and requires detailed technical work, so it should be a strong sense of responsibility by the skilled personnel in the

connection line, the first way to ensure that the requirements of the state without power, because audio and lighting equipment,

power supply requirements different, if the installation provides the power, not only poor security, and very easy to damage the

equipment; Second, the required construction standards in line with electrical installation, electrical installation standards as way to

test whether a reasonable standard, in accordance with standard construction or not, up phase of the project quality is completely

different, many of the formal construction in accordance with standard engineering expert to see that job done, "beautiful";

Furthermore, for a range of connectors, a large variety of projects required to two core, three core, Lotus connectors, XLR plug,

multi-pin connector with a very large, often several people while making a very long time to complete, if you do not know the correct

connection before welding methods and welding methods, can be imagined know, how much trouble will come back to Qigong, it

must be clear, for example: some European foot XLR audio products, and not the same as the number of general use, do not weld

the wrong; some of the light shielding requirements of the control line high, If welding is unreasonable, it is possible to make the

lights malfunction; finally asked all of the firing line, zero line, ground and shield connections must be accurate, the power supply, we

should note that: sound and lighting Some devices use power to often lead to misunderstanding, for example: Some devices use

110V AC, while the transformer is a separate plug-random, if it is forgotten when the connection line, and directly to the device is

plugged in to 220V power supply , the consequences can be imagined; another example: Some peripheral devices use low-voltage

alternating current, but some use low voltage DC, and their appearance is very similar to the plug, if not careful, after power-on light

for those who cause the sound to the anti- offset, reducing the sound pressure, sound quality deterioration of the consequences,

but also easily lead to the equipment enclosure charged, leaving the security risks; from the shielding in terms of network anti-

interference ability of the system, mainly on the system is properly shielded and shielded the person does not work, will be severe

damage to equipment, and supply line phase error may affect the speaker phase, which has the correct level of quality and shielding is

often found in a number of projects: either no mask or shield form a closed loop circuit; or shielded cable is shielded form the network

error can not resist without interference, and even some of the works of construction workers and power of the signal to zero, the

shield and the signal line confusion, casually connected, not only anti-interference, but also will bring a lot of interference, so be sure

to actually put these concepts to understand clearly.
6, the installation, power lines, connecting the inspection
Because the entire system is involved in sound engineering the connection point and the connectors are more likely when the

installation causes an error because the individual, so careful examination is necessary, the general security checks, including

equipment installation, power supply line is reasonable, the connectors are connected correctly and so on, there is another important

item to check is: carefully check the status of each piece of equipment set meets the design requirements, this must not be

forgotten, or easily result in equipment damage These states include; amplifier in bridge requirements, bridging switch is set; the

device s power switch is the right choice; lighting device is voice or electronic control; scanner address code is set correctly; projector

input settings, etc..
7, device debugging
For equipment debugging, because each project is different, difficult to unify a common approach, requires a separate category for

discussion, if it is to complete a comprehensive project for all types of debugging are introduced, the length will be too much, here

only commissioning of engineering equipment in general simply described.
A. Preparation prior to commissioning
Sound engineering debugging is a need both skills and experience they require careful and meticulous work of the spirit, when the

design and construction are in line with requirements, detailed debugging is not unreasonable, not only can not achieve the design of

the project results, but also may devices operate in the abnormal state. Therefore, before commissioning to fully understand the

importance of this work. Confirm carefully before commissioning of each piece of equipment is installed, properly connected, seriously

to ask construction workers left the construction may affect the use of the problem; carefully before commissioning confirm each

piece of equipment is installed, properly connected, the construction workers to ask serious legacy that may affect the use of

construction related problems; debugging again before carefully read all of the equipment specifications, design drawings carefully

check the label and connections; pre debugging must be sure that power lines and power supply voltage without any problems; pre

debugging should ensure that the site not related personnel; before commissioning but also to prepare the appropriate equipment

and tools.
B. Sound system debugging
Sound system debugging is the key to project commissioning, sound system equipment involved in most debugging is also the site of

the largest problems may also be up, so first of all concentrate on it. Need to prepare the equipment and tools: phase analyzer, noise

generator, spectrum analyzer (with sound level meter), meter and so on.
Debugging steps: separate boot device from the audio signal transmission gradually checking the situation, the check makes sense,

because only the signal transmission of sound in various devices, amplifiers and speakers will be a normal process to go through the

correct signal it possible to have a good sound, so do this step work, we must be patient, we must carefully carry out this step, the

speaker and amplifier connected to the first do not worry, the best place around the processing equipment is also bypassed the

state. Check the whereabouts of the signal to follow the step by step down the signal to check the whereabouts and gradually

check its level set, gain, phase and flow conditions, ensure that all equipment can be the best first-class equipment to provide signals,

but also provide the best signal for the lower, while checking the signal, it should also step through the level set, gain, phase and flow

conditions, ensure that all equipment can be the best first-class equipment to provide signals, but also for lower provide the best

signal, check the signal at the same time, it should be one by one observation equipment is working properly, is stable, the

significance of this work is that a single device failure or unstable at this time, more convenient to deal with them, nor would

endanger the safety of other devices, so that the check should not be brought into the next step. After the above is correct, it will

access each speaker and amplifier system, the smaller the volume, the use of phase one by one instrument first check speaker phase

is consistent, prepare for the following commissioning, the noise generator and equalizer access systems , the spectrum analyzer is

ready to moderate the volume of the system began to access the equalizer, spectrum analyzer is ready to begin a moderate volume

balance of the equalizer debug, spectrum analyzer test points selected in accordance with relevant standards, the equalizer

commissioning principles are: the spectrum analyzer is 20Hz ~ 20kHz audio range frequency response curve shown in the hall at the

base of each test point straight, pay attention: when tested on the various points to make the volume consistent, then record a

good debugging equilibrium after each frequency potentiometer position; the same to a smaller volume and a larger volume is

consistent, then record the equalizer after a good debugging the frequency potentiometer position; the same to a smaller volume

and larger were once again the volume of debugging, and then the equalizer debug results recorded, the final results of the

commissioning of several data analysis, to find a variety of volume levels are a measure of the frequency of the compromise position,

and then test and frequency response curves depicted down the hall, the final equalization of the frequency position should be

recorded, note: debugging in the equalizer, mixer frequency compensation must be placed on 0, and other peripheral devices to in

the bypass state, the other should be noted that: in the usual audio project, taking into account the halls of the decorative material

to absorb the high frequency signal is weak, it may be appropriate to do a little signal above 10kHz attenuation.
After the above steps, there should be electronic crossover debugging. Debugging can be divided divider high, medium and low-

frequency alone, which divider in the system for different purposes. Debugging methods are different, if, just for the subwoofer

crossover frequency, and that as long as the balance in the debugging is completed, let the bass speakers work alone, the bass

crossover frequency divider 150 to take 300Hz between bass signal appropriately adjust the gain, can feel the bass level is

appropriate, then an audition with the full-range system, then bass and smooth full-range volume; if the divider used in the full-range

system, requires accuracy provided by the manufacturer in accordance with sound parameters are set high, medium and low

frequency crossover point, and then repeated for each frequency band signal gain adjustment, until the band s sense of hearing more

balanced, and then refer to the next step in the test spectrum analyzer sound pressure of the test point for further fine-tuning.

Equalizers and electronic crossovers to be the basic commissioning is completed, you should begin the determination of sound

pressure level of the hall, the original selected test point or points, noise, pink noise source device should be used, in addition to

testing the whole band, the as far as high, medium and low frequency bands were selected several tests of the goal is: to ensure the

best dynamic signal under the premise of making the system to adjust the sound pressure in the expansion of the points should be

designed to achieve sound pressure level at the same time to refer to high, medium and low frequency of the spots, and then were

on the equalizer and the electronic crossover slightly adjusted, if the results of each test point deviation of sound pressure level

greater uniformity of the sound field well, it should be carefully analyzed and the corresponding improvement, the first from the

architectural aspects of the construction process, if it has a large flaw, which affects the quality of the sound field, it should make

possible corrective measures: if no obvious decoration defects, or have some deficiencies, but can not be improved, it should be from

the speaker s placement, and installation in the form of points were analyzed, the analysis include: the speaker and the building is

surrounded by the distance, speaker of the between the installation site, the speaker points and frequency characteristics, the

following projects under actual common speaker placement, use of the icon to install some more.
Below the microphone and the effects of debugging, the debugging for the microphone, you can classification, vocal microphone

with a cable line as long as there is no audible noise, the sound quality can be normal, and in its effective range of the sound

spectrum analyzer can be used for feedback frequency of monitoring, and prepare the appropriate frequency and location of records;

instruments used must be wired microphone with the East team a debug, and make use of each instrument model and pickup from

the microphone records; wireless microphone and the band a must with debugging, and make use of the instrument and microphone

pickup models the distance record; wireless microphone debugging to note: the antenna location and reasonable use of the

microphone position appeared dead (well records), gain of the receiver signal level can be appropriate , fine-tune the noise to find the

best place to be repeated and so on.
For the effects of commissioning, the principle is to ensure that the input signal gain, can get a better dynamic effects, sound signals,

and to leave a margin, the effect is mixed-signal output is set according to demand. As for the effects of the specific effects of

selection and parameter setting, should make some rough trials, and then selected according to the requirements of the program,

just to note are: effects of reverberation time and the delay in the transfer time should not exceed the amount of certain range, so

as not to affect the language of clarity and continuity of the signal, the microphone and the effects of commissioning, the system

should also include the debug back to listen to, in principle, is: listen to the system to return to the main sound system frequency

response characteristics and the same, The sound pressure level actors (including the band) can clearly hear the voice of their

subject, not too much, can not bring additional sound feedback.
Pressure limiter for debugging, the system should be set above the device and then transfer to the basic, general engineering, the

pressure limiter is to protect the amplifier and speakers, as well as the voice box, and make smooth changes in the sound, so

commissioning of the first to set the starting level of compression, usually do not set too low, too high of course, will also reduce the

protective effects, depending on a variety of specific settings should be limited to the regulating pressure range and signal the case

may be, and secondly to set the compression boot and resume times, usually start-up time should not be too long, so as not to

protect the action is not timely, and the recovery time should not be too short, so as to avoid damage to the sound effects; Another

thing is to set the compression ratio, the general engineering design, including 4 : 1 or so, the pressure limit of noise in the door it is

set to pay attention: If the noise is not large doors closed; if there is some noise, the noise gate threshold can be set lower at the

level to avoid extended the phenomenon of intermittent acoustic signal, if the system s noisy, it should be analyzed from the

technical aspects of construction, the door can not be solved alone by the noise, other settings according to different requirements.

Other equipment is no longer for 11 debugging detail, in general, the principle of debugging, you must carefully read the product

descriptions, detailed step by step to fine-tune, without undermining the basic premise of sound field conditions, the selective use of

audio processing equipment to meet the design requirements.
C, the overall commissioning
When commissioning the system were completed, and confirm all equipment in good condition, no obvious debugging is not the

time, you should begin a comprehensive commissioning of the entire system, with each device individually test each system is

different is that there is no comprehensive overall commissioning specific parts of specific adjustments, it is primarily the task of co-

operation in the system, check they are interconnected and part of the work is coordinated and check whether they will work in a

mutual influence and interference.
D, system simulation run
After debugging the system, the formal process must be carried out before running the system simulation is run, no matter what the

size of the sound system, larger than the number of its equipment and work status also varied, coupled with the quality of equipment

and work systems stability inevitably uneven, the project in a short time debugging, it is difficult to discover the hidden or less, but

once the project is completed, the actual running time of the system much longer, often well over time, running overload

phenomenon, when the system already exist and undiscovered hazards and deficiencies, it is possible to rapidly expand, both to users

and adversely affect engineering, simulation run is to actually run in a similar environment to understand the system works situation,

identify problems and take preventive measures.
First, to measure the overall system operation and run a separate power supply line when the current of each phase.
Although the design and construction of power lines for the corresponding requirements of each phase of the current distribution has

also been a general understanding, but the actual operation will certainly be different from the theoretical value, in order to be aware

of, foolproof, actual operation must be measured when the current situation, the general flow table clamp can be used for each sub

-phase time points were measured the number of devices to run, if you find the actual measurement value and there is a wide gap

between the theoretical value, or the ratio of the phase current a big gap between the line currents or extraordinary situation must

be re-rectification to ensure safe use of electricity.
Second, we must check all equipment at full load operation and long-running job stability.
Professional sound system and a non-professional sound very different, is that they run at full load conditions and for a long time,

showing a very different job stability, job stability has become an important professional audio and lighting equipment performance.

But even with the professional equipment, the stability of each other s work also vary widely, some of the equipment in very poor

conditions still work, some of the equipment is in working long hours and worrying. These checks include: changes in sound quality,

wireless microphone frequency stability and when the battery is not enough acceptance, the equipment, working long hours and

noise circumstances. However be noted that: job security check is to ensure that equipment is in reasonable conditions as the

prerequisite, not intentionally make the equipment to check the working environment or to the equipment in working condition is

not normal to do so due to equipment damage is not warranty.
Finally, check all equipment at full load operation and the heat of a long running time.
Are basically sound system equipment power equipment, the operation will certainly be different in the degree of fever, especially in

high-power devices such as amplifiers, the heat conditions are usually more obvious, so a certain degree of heat, which is not

equipment and systems would be, what impact the safety of equipment. However, if the installation did not keep adequate space for

heat dissipation, or the device itself in the long, heavy-duty heat dissipation running bad, then that to be resolved, otherwise the

light to produce a protective device, causing severe damage to equipment. Within the normal scope of work equipment heat serious,

be sure to equipment replacement; if no suitable space for heat dissipation and heat equipment is large, forced ventilation should be

considered, and to explicitly tell the user; to regular dust cleaning and equipment maintenance .
Also to add is: generally carried out in the simulation run under different loads, different times of system commissioning, further

examination system job security and stability.
In short, the system is very important to run the simulation is very necessary work, then work in exchange for each of the devices will

be stable and long-term operation of the safety systems work. Power lines and equipment, especially the heat conditions, will be

directly related to the safety of the works, so should cause all the engineering and technical staff are highly valued.
E, debugging results and problems of record
Because sound engineering to debug, set and check the project a lot, and these results and question the future use and

maintenance is an important reference information, it is necessary to work during every step of the results and will record the

problems and then make the necessary analysis and summary. Useful for recording user data, should be handed over to them; useful

for future maintenance of records of data, should be properly kept by the designer. Record results, including: equipment location

number, the device configuration status, debugging of test data, edit the relevant program information, etc.; records include:

equipment, work environment issues, equipment interference problems, equipment operating conditions issues, and sound work-

related problems but affect system operation and so on.
Fourth, the difficult engineering problems
As a complex multi-technology types of broadcast sound engineering that may occur during a variety of problems, coupled with sound

and lighting system, a larger number of equipment types, and the system s technical requirements vary widely, so the occurrence of

various problems inevitable, and usually will encounter some difficult problems. According to the characteristics of sound engineering,

engineering design and progress of the project s quality plays a major role, so long as in the construction of carefully designed and in

accordance with the relevant specifications are generally not encountered in the construction process difficult problems, or that these

difficult problems will not be reflected in the construction. In most of the time, the difficult engineering problems in the debugging

stage, even after a period of time shown. Since it is a difficult problem to solve is not easy, often painstaking examination of a long

time, always remains; at some time the problem somehow disappear on their own, and then when they do not know what

happened, which makes people a headache, Each one must work in audio engineering and technical people will have different levels

of experience. But while these kinds of difficult problems is the form, but as long as the design is not an error, we can say that the

root causes can only be one; construction aspects of oversight caused. So, even difficult problems, or can be solved.
The following is a common part of the typical difficult problems.
1, the phenomenon of the equipment enclosure are charged
As the sound engineering of all electrical equipment must, so debugging may first encounter some of the equipment enclosure

charged, although not necessarily affect the case charged the use of equipment, but will endanger the safety of users, must be

completely resolved.
2, the sound system volume less than
Projects often encounter when debugging the volume of sound is always small, less than the design requirements of the

phenomenon of sound pressure level, which indicates the device on the installation and setup problems.
3, the sound field in the resonance and feedback
Although the design and construction when they were seriously considered, but inevitably there are not very thoughtful and

unpredictable place, and that this problem occurs affirm that people of normal use, should be eliminated.
4, interference noise
Sound engineering noise interference encountered a lot of time, the causes are different, very often to solve the trouble, but as long

as careful analysis of the construction from the system to find a cause, step by step analysis, the problem can always be resolved.
5, the wireless microphone sound instability
Most projects are now equipped with a wireless stereo microphone, but due to improper installation and commissioning, use a

significant number of poor, especially in live performances, the work of the wireless microphone will directly affect the quality of

performance, so this is not a ignore the problem.