Many friends who have installed a home theater will struggle with whether to install a subwoofer. The main reason for this confusion is that they do not know enough about subwoofers. When we go to the cinema to watch movies, in addition to the attraction of the big screen, it is the sound The stereo surround is clear and heavy, including the interpretation of many songs on the stage, and the dynamic sound quality in the car, which is inseparable from the contribution of the subwoofer. What is the use of a subwoofer? How to install a car subwoofer? Let’s find out together.
1 The principle of the subwoofer
The principle of the subwoofer
The internal power amplifier circuit divides the sound into several frequency sections through the frequency divider, and the output of the middle and high frequency sections To the satellite speakers, the low-frequency output is sent to the subwoofer. Generally, the subwoofer emits a low-frequency sound of 20-200HZ, which is transmitted through the reversing hole and resonates with the satellite speaker speaker, and the bass effect is very shocking.
Types of subwoofers
Active subwoofers refer to subwoofers with built-in power amplifiers, no need to add power amplifiers when using them, usually in the shape of a barrel. Mode. The disadvantage of this subwoofer is that the heat dissipation is not ideal and the power is not very large, and the barrel shape usually produces unnecessary resonance, which reduces the controllability of the subwoofer.
In contrast, passive subwoofers require an external power amplifier to work. The shape and power selection of this subwoofer can be more flexible, and the effect is naturally more ideal. In addition, active speakers can be further divided into sealed boxes and punched boxes. The former is more suitable for deep symphony, and the latter is more suitable for pop music.
2 Subwoofer function
Adding a subwoofer (especially active) to the original sound system will greatly increase the dynamic range of the system and allow the low frequency to dive deeper. At the same time, the transparency of the mid-frequency will be better, and the sound can be more resonant without being restricted.
With the addition of boost power and subwoofers, the sound system is able to reproduce music peaks at higher levels. And because the main speaker is no longer responsible for the task of reproducing bass, it can play with a louder sound. Because the cone of the main speaker’s woofer no longer needs to move back and forth as violently as before, the midrange will be clearer when it is used for music playback.
3 The difference between an active subwoofer and a passive subwoofer
The difference between an active subwoofer and a passive subwoofer
1. The difference between whether it has a power amplifier
Active speaker: built-in power amplifier circuit, it can work after connecting the power supply and signal input. For example, most of the speakers used in computers are active speakers.
Passive speakers: There is no power amplifier circuit inside, and an external power amplifier is required to work.
2. Differences in market positioning and consumer groups
Active speakers are simple audio systems, mostly used in the field of computer multimedia, with low output power.
Passive speakers are formal speakers with high power and good sound quality, but they are bulky and bulky.
The difference between a subwoofer, a speaker, and an amplifier
A subwoofer specializes in the bass part, unlike a woofer. Something more shocking or dynamic can be provided.
Amplifiers are used to power speakers.
The speaker is the sound, which is distinguished according to different characteristics (speaker size, line characteristics). For front, left and right main speakers, rear surround, etc.
4 subwoofer speakers purchase
1, power:
It determines what the subwoofer can emit the maximum sound intensity. Depending on the rated power, there are currently two ways to label the power of subwoofer speakers: rated power and peak power. The higher the signal-to-noise ratio, the better.
2. Cabinet material
When choosing speakers, weighing the components is a very important step. If a large wooden speaker is very light, its performance will not be much better.
3, diaphragm material
The diaphragm material refers to the manufacturing material of the speaker diaphragm. If you like string music, choose paper, wool, metal, polyethylene, and bulletproof cloth. In the south, use paper and wool as few as possible, which are easy to absorb moisture and change the sound quality.
4, speaker unit diameter
The speaker unit diameter (bass part) is generally between 2 and 6 inches. Within this range, the larger the aperture, the higher the sensitivity and the better the low-frequency response.
5 Installation method of car subwoofer
Installation method of car subwoofer
1. The power supply cannot be connected incorrectly, the wrong connection will cause the power amplifier fuse to burn out, and it will burn if it is serious. Bad amplifier board.
2. The 12V power amplifier of the car subwoofer belongs to the positive pole of the power supply. The car owner directly pulls the wire to the positive pole of the battery and installs the fuse.
3. REM belongs to the control line, generally found on the control line of the host such as DVD/CD/MP3/MP5/, at the end of the host.
4. GND is the ground wire. Generally, the ground wire should not be too long. The contact surface with the car should be cleaned to avoid current noise.
5. After the installation, the owner should adjust the volume of the car subwoofer. The volume should not be too large, and it should match the audio system.
How to connect the subwoofer to the computer
Only one audio cable with 3.5 three-pin plugs on both ends, one of which is plugged into the LR IN socket of the subwoofer On the hole, the other end is inserted into the middle one of the three 3.5 jacks on the computer case (the green jack).
What kind of music is suitable for the subwoofer
The subwoofer is a super bass speaker, so it is more suitable to express some music with heavy bass, such as DJ, which is mainly suitable for rhythm Music that pleases the listener with a strong or mostly rhythmic sense.
6 Active subwoofer test debugging
Regular test:
Adjust the volume to the minimum, the frequency at 12 o’clock, and the phase is random. Choose a CD song (not DVD) with rich low frequency, and choose one of the R and L signals of the disc player to directly connect to the R or L channel of the gun, or connect both. Turn up the volume slowly, the gun will definitely emit low frequency, and experience the change of low frequency components in the room from low volume to high volume. Adjust the volume to an appropriate position, and then adjust the frequency knob, from 20HZ to 150HZ, to experience the dive depth and frequency changes of the gun. Check if the cannon is sounding normally.
Coordination and debugging:
1.Enhanced2channel system Bass connection method
Connection method 1: Connect the left and right signals of the audio source (CD or DVD player) to the left and right signal input ports of the gun, and then connect the signal output of the gun to the power amplifier, and the power amplifier Push the speaker, the signal flow chart: audio source – gun – power amplifier – speaker.
Connection method 2: If the audio source has 2 groups of signal output or adopts 1:2 signal line, one group is connected to the gun, and the other group is connected to the power amplifier.
Adjustment of the gun: The frequency is adjusted according to the caliber of the speaker. If the caliber is large, it can be adjusted as low as possible. Otherwise, it can be adjusted up. It depends on personal preference, and there is no unified standard. The phase switch whichever has better bass effect is selected in that position, and the volume is matched with the main speaker.
2. assume5.1system’s0.1channel subwoofer amplification
Connection method 1: The AV power amplifier with decoding has subwoofer signal output, use a gun wire (preferably one-to-two gun wire) to output the subwoofer signal of the power amplifier When connecting to the gun, the frequency of the gun with this connection method can be increased as much as possible, and the volume can also be adjusted to a larger point, because the signal is limited by the AV power amplifier, and the operation is also convenient.
Connection method 2: The DVD player with decoding also has a subwoofer signal output. Use a gun wire (preferably a two-part gun wire) to connect the DVD player’s subwoofer output signal to the gun , the frequency and volume of the gun using this connection method should be coordinated with the main speaker and the center surround. Generally, the frequency is adjusted at 12 o’clock and the volume is adjusted at 3 o’clock, but there is no uniform standard.
7 Maintenance of common faults of subwoofer , the line can be disconnected and reconnected or replaced. If the fuse and power cord are OK, check the AC adapter or switching power supply circuit.
High current sound
High current sound will cause no sound or affect the sound output. If there is a large current sound, it is caused by the AC transformer problem or the failure of the capacitor, and it can be solved by a replacement.
No Treble
If there is no treble and only bass, it means that the treble processing IC cannot work. Priority is given to replacing the audio processing chip, such as 4558D is the most common. If it doesn’t work after changing the audio processing chip, check the relevant working circuit.
No bass
No bass means that the power amplifier tube is not working, first replace the power amplifier tube, and then check the relevant circuit if it fails. Amplifier tubes commonly have three legs and seven legs.
Lower sound
Either there is a problem with the control circuit or the processing circuit. The control circuit mainly checks whether the potentiometer switch is in good condition. The processing circuit mainly checks the related circuits of the audio IC and the power amplifier tube.
Poor bass
Mainly because the woofer is not installed and fixed or the quality of the woofer is deteriorated. Replace the woofer.
