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Knowledge collection of professional amplifier(人气: 407) 
Release time:2018-05-30

A qualified professional amplifier often meets the corresponding technical parameters. The following 8 technical indicators can not be ignored.

1, the frequency response capability (Power Band Width): the frequency response range is 20Hz to 80KHz, and the frequency response of the horn is required to respond to the range of 20Hz to 20KHz from the bass to the high tone. As the "bottleneck" part of signal transmission, the power amplifier requires a wider frequency response, such as 7Hz to 80KHz, so as to ensure the integrity of the signal.

2, signal to noise ratio (Signal To Noise Ratio): This is the most direct reflection of the parameters of the quality of the power amplifier, generally in the ratio of 80dB above, high quality products are often more than 105dB, if you pursue the sound quality of pure, then this value can not be ignored.

3, distortion (THD): this can be discussed in conjunction with the other two important indicators of power amplifier "rated power" (Rms) and "maximum power" (Peak Power). When a power amplifier works in its Rms power, its distortion should be relatively small, generally ranging from 0.5% to 0.01%. When Peak power or bridge connection, the signal may produce distortion, clipping (incompleteness of the sowing signal) and so on. The ratio of distortion will increase, and about 0.5% ~ 1% are normal. The smaller the distortion ratio, the better the sound effect is, and this is also an important index to measure a power amplifier.

4, input sensitivity (Input Sensitivity): This is for different manufacturers, different brands of host, pre - level sound source setting level, range from 100mV to 4V or even higher, the tone should be matched with the sound source.

5, input impedance (Input Impedance): generally requires high input impedance of power amplifier, low output impedance and higher input impedance, can effectively block all kinds of noise, the common value is 10K Omega or higher.

6, load capacity (Load Impedance): the home power amplifier is generally two kinds of 8 ohms /4 omega; the car power amplifier is 2 ohm to 8 ohms in stereo, and 4 to 8 ohms at bridge. However, the impedance of some specially designed power amplifiers can be as low as 0.1 ohms. At this time, a power amplifier, and can be connected with dozens of bass units, to create an ideal sound pressure level (sound pressure refers to the pressure produced by the sound of the human ear, it is the standard to measure the ability of the sound system, because the higher the sound pressure is, the higher the demand for the system, the more the highest record in the country is 141.5dB, and the foreign 176.5dB). Just like those dozens of woofs in the car, the van that can shake the glass, but this scene will probably be seen in the sound competition.

7, working voltage: car audio is generally in the range of 10V to 15 V in normal work.

8, the damping coefficient (Damping Factor): the coefficient is calculated by the output impedance of the rated load (4 omega). It is generally believed that the less the output impedance and the higher the damping coefficient, the better the power amplifier. In fact, high quality amplifier, most of the ratio is more than 50, individual or even more than 500, although some experts think that the damping coefficient of about 50 is enough, but in my personal experience, the coefficient is high, then the wire requirements can be relaxed. Relatively high coefficients will affect the timbre but help the bass performance.

9, conversion rate (Slew Rate): the highest amplification level of power amplifier in unit time magnified the strong signal excitation to high voltage, strong current of the ability to communicate audio, high grade machine 30V/us above, individual super 50V/us. The ratio is high, the conversion ability is good, the music level and dynamics, when combined with the loudspeaker, it can be closer to the original sound to restore and reproduce.

The combination of power amplifier and loudspeaker

The combination of power amplifier and loudspeaker is mainly power matching and style matching.

Power matching: if you are the first player to play the stereo, and you want to DIY instead of others, I suggest the same Rms power match. First, it is not easy to explode the horn, and it is not easy to burn the coil. If you are a good player and have plenty of economy, it is also worthwhile for the "big horse drawn cart" to use the powerful power amplifier to push the horn and pursue the detailed timbre.

Style matching: Japanese and American equipment consciously compensate for low frequency and high frequency, and the sound is often not as good as European product balance. The taste is different.

Installation of power amplifier on car

The introduction must have made you realize the importance of power amplifier to the whole sound system. As the power amplifier works hard in the sound, it is very important to ensure the normal operation of the amplifier.

First of all, to install power amplifiers on the vehicle, in addition to considering the matching with speakers, the supply of electricity, including wire considerations and reasonable wiring, should be paid attention beforehand. Installation, all kinds of wire to avoid short circuit, the best insulation installation, such as adding density board (this is a special board, often made of sound box, also known as wood bran board), to avoid direct nail on the body iron, concurrent noise.

At present, the installation technology of car stereo, especially the design of Hi-end class, often pays great attention to the installation process, and the system layout of the trunk is beautiful. The charm of the power amplifier is shown artistically through exquisite workmanship. This is not just a pleasing pleasure, but the technical requirements are very strict.

Brand power amplifier one by one

In the increasingly mature market of car audio in Shenzhen, products with simple parity, poor quality, or good quality but single functional technology can no longer meet the requirements. In addition to good sound quality assurance, a variety of functions are essential, such as power amplifier, in addition to its own good power amplification function, it is necessary to have high efficiency protection circuit technology, improve power, guarantee sound quality of high fidelity technology, or even advanced frequency division, sound color balance circuit, in order to improve the cost performance, It is popular and highly praised by people, especially DIY, so the big car audio manufacturers conform to the trend of the market, and the design and development products are versatile, simple, safe and accurate. Here are several excellent tables for you in sound quality, function and installation operation. Now the world class power amplifier brand.


ALPINE is a well-known Japanese manufacturer in the field of sound. Its series of products have unique technology and irresistible charm that other brands do not have. Its design is mostly with silver gray and gray ink as color style. In terms of internal technology, ALPINE pioneered the design of the "V12" processing technology that is most suitable for 12V running voltage. What's unusual about the technology is that even at 12V voltage, power amplifiers are still able to achieve maximum power and guarantee sound quality rather than power supply for 14.4V (ordinary car Amplifiers need this voltage to perform the maximum efficiency, so their performance is to be discounted, but ALPINE's V12 is finished with 12V. " Full capacity).

In addition, ALPINE's Bass Engine circuit is designed to use the output, input balanced circuit, specially order large capacity capacitors, so that people are sighing for the improved product performance, the uncompromising "revolutionary spirit", the new ALPINE power amplifier has adopted the above technology, and even the ALPINE is proud of the low. Anti technology and high current protection circuit, which makes full play of the amplifier's efficiency, is also effectively protected. A new current circuit to achieve a steady current. The parallel winding De-De large transformer is more stable, such as stone and stone, to enhance the power supply capability of the system, effectively reduce distortion, and has a high reputation of the brand.

ALPINE Advanced Series (MRV Series) amplifier, two channels such as MRV-1507, bridging RMS power up to 900W, peak 1500W above, amazing power. The four channel represents MRV-F407, RMS60W x 4, using hi fi equipment.

Rockford fosqate

Rockford fosqate, the king of car audio from the United States, has won awards for its design and production of power amplifier in the international auto audio League (IASCA). Its high current low impedance patent "TRANS.NOVA" technology circuit is of high quality.

In order to ensure the good performance of its products, Lai Fu company was a founding member of IASCA. In 1980, it set up the R.T.T.I of Lai Fu Technical Training Institute (R.T.T.I). Therefore, when your rifle sound system is completed, you will have more insight into its outstanding performance and good technical services.

The power series, called "bombers" in the Lai Fu products, such as power500a2 and power800a2, are all powerful "bombers", which can be as low as 0.11 omega and drive dozens of bass speakers, and the sound quality is still excellent. Its "TRANS.NOVA" circuit ensures the reproduction of the original sound. Efficient and secure NOMAD (non multiplication advanced judgement circuit) ensures that the power amplifier will not damage at peak condition. In addition, this remarkable performance also benefited from MEHSA's efficient heat dissipation technology.

Lai Fu sound series PUNCH, using a large number of lucky patented technology. The "INDIGO" ensures the best output in any power state; "TOPAZ" eliminates the grounding loop and solves the noise. The representative models are Punch 400a2, power200a2, etc., with 12dB built-in high and low frequency division function, which is quite good power amplifier.

Fiery dragon

Dragon Motor audio amplifier is a product designed and manufactured locally in Italy. Its timbre is pure and pure. No matter listening to folk songs or rock music, it also laments its extraordinary skill. Fire dragon power amplifier surface adhesion technology to implement efficient quality control, the design of the implementation of the "small size size to achieve high power", its special circuit technology can eliminate the difficult switching noise. All the power amplifier of the fire dragon can achieve "multi mode" connection, that is, without the need to add another power amplifier, it can simultaneously realize the output of the stereo front and the single sound mode of the overweight bass (one of them can only be achieved), without the need to add a power amplifier to achieve a broad sound field effect. The electronic frequency division network built in the power amplifier can freely select different frequency points between 80 or 120HZ for Qualcomm HP, of course, it can also achieve full pass Fullpass. Such as four channel power amplifier DA-604. If you need more play, then the DA-606 six can satisfy you.

The dragon is also equipped with air-cooled DB series, with a pale blue tone. The design of efficient air-cooled design has the feeling of being friendly and upscale. DB-505 five channel amplifier is the first choice of AV amplifier for car audio.


PPI is a burning product from the United States. The shape is very smooth, aluminum casting shell, high efficient heat dissipation fan, line is high level double circuit design (circuit board two sides of the design of different circuits), the components are very high, using DSM surface bonding technology (special bonding technology of electronic components welding), separate components, machine press welding, built-in frequency divider, each The frequency division orders have accurate frequency points. This is an indispensable passion for enthusiasts, especially the promotion of Q-BASS's bass, so that you can enjoy the bass fun more easily.

Common high power monster PC-1800.2 and PC-21400.2, of which PC-21400 is rated power of 1400W, more powerful than many large professional audio. The four channel has 60W * 4 PC-4400, 40W x 4 PC-4200. The six channel has a Q-BASS function of PC-6600. Its price is comparable to that of the same power. The thick tone and meticulous are the outstanding features of PPI products.