What does subwoofer mean? How to choose an entry-level subwoofer? This is undoubtedly very difficult for many users who are new to audio systems. But when you get here, you don't have to worry about it. Next, the author will systematically introduce you the relevant knowledge of the subwoofer and how to choose a useful subwoofer. Interested friends do not go away.
1. What is a subwoofer
A subwoofer, also known as a subwoofer, is a type of speaker used to enhance the bass output of a wide-band speaker and try to make the bass dive deeper. With it, it can make the restoration of the program source more solid, without it, it gives people the feeling of lack of power and energy, and the tweeter reflects the details of the sound.
Second, the principle of subwoofer
The internal power amplifier circuit divides the sound into several frequency bands through a frequency divider. The medium and high frequency bands are output to the satellite speakers, and the low frequency bands are output to the bass.
Generally, the subwoofer emits low-frequency sound of 20-200HZ. It is difficult for people to hear when the energy is not strong, and it is difficult to distinguish the direction of the sound source. Such low-frequency sound is transmitted through the inverted hole and resonates with the satellite speaker. The combination of the weak bass generated by the speaker and the satellite speaker speaker will re-enable the performance speaker to release the bass, so the bass effect is very shocking, and it makes people feel the same as the satellite speaker speaker.
Three, the role of the subwoofer
Adding a subwoofer (especially active type) to the original sound system will greatly increase the dynamic range of the system and make the low frequency dive deeper. At the same time, the transparency of the intermediate frequency will be better, and the sound will be more unrestricted and louder.
Due to the increase of the driving power and the woofer, the audio system can reproduce the peak of the music at a higher level. And because the main speaker no longer bears the task of reproducing bass, it can reproduce with a louder sound. Furthermore, because the cone of the woofer of the main speaker no longer needs to move back and forth intensely as before, the midrange will be clearer when used for music playback.
However. There are advantages and disadvantages, and the subwoofer also has its disadvantages. From the perspective of music appreciation, adding a subwoofer often makes the performance of the audio system worse when replaying music. The reason is that most of the subwoofers are not well-designed and made; or they are adjusted and erected improperly; or they are just to have a very powerful bass effect when used in a home theater system. In short, I don't want people to hear the subtle details in the music.
Fourth, the classification of subwoofers
Subwoofers can be divided into passive subwoofers and active subwoofers.
1. Passive subwoofer
Passive subwoofers only have one or a few subwoofers in the speakers, which is no different from ordinary speakers. It just needs to be driven by an external power amplifier. But there are some subwoofers that can share a power amplifier with other speakers.
In this compelling household method, the broadband output of the power amplifier is also added to the subwoofer, and the crossover network in the subwoofer needs to be used to separate the low-frequency signal from the audio signal and add the rest after filtering. To the main speaker, this method requires adding a crossover network to filter the speaker level signal in the signal path.
2. Active subwoofer
The active subwoofer combines a woofer, a line-level crossover network and a power amplifier in the same speaker, so no other chassis and other power amplifiers are needed. The speaker has a line level input terminal for the input signal of the preamplifier, the line level output terminal of the power amplifier and the volume control of the speaker.
Five, the evaluation index of the subwoofer
It determines the maximum sound intensity that the subwoofer can emit. What we need to look at is the rated power. You can also query the model of the power amplifier module, and then query the output power of the module, which is the output power of the speaker. At present, there are two ways to label the power of subwoofer speakers: rated power and peak power. Signal-to-noise ratio: the higher the better.
2. Cabinet material
The current subwoofer speaker material is divided into two types: plastic and wood. It was generally believed that wooden speakers are better than plastic speakers, but the current idea is not perfect. The sound quality of some well-made plastic speakers is far better than that of shoddy wooden speakers. Therefore, weighing the weight is a very important step when selecting speakers. If a large wooden speaker is very light, its performance must not be much better.
3. Diaphragm material
The diaphragm material refers to the manufacturing material of the speaker diaphragm. Among them, the diaphragm materials of the tweeter include plastic film, silk film and metal film; the diaphragm materials of the woofer include paper cone, polyethylene cone, wool cone, aluminum-magnesium alloy cone, and bulletproof cloth cone. These materials have different properties, and the prices are high and low. It is difficult to say who is better and who is inferior. You like string music. Choose paper cones, wool cones, metal music cones, polyethylene cones, bulletproof cloth cones, and paper cones and wool cones as much as possible in the south. Use less, easy to absorb moisture and change the sound quality.
4. Speaker unit caliber
The speaker unit caliber (bass part) is generally between 2 to 6 inches. In this range, the larger the caliber, the higher the sensitivity and the better the low-frequency response.
6. Precautions for purchasing subwoofer
1. The size of the subwoofer is not the bigger the better
Many beginners who buy a subwoofer think that the bigger the better, it is not the case. The larger the unit of the subwoofer, although theoretically it can bring a lower dive and sense of volume, but that is theoretical. A 15-inch 2,000 yuan subwoofer can hardly be better than a 12-inch 8,000 yuan subwoofer in terms of data and sense of hearing. Therefore, the more basic the subwoofer, we recommend that you choose a small cannon instead. Because of the same price, small-sized products have more materials than large-sized products, and the sound of a smaller unit is easier to control. A cheap large-size subwoofer, it’s better not to buy it!
This one is big enough and cheap, it is a waste to use in home theater!
2. The greater the power, the better
The greater the power, the better the driving ability and unit control ability. When choosing a subwoofer, pay attention to its standard RMS power, which represents the rated power that the subwoofer amplifier can output stably for a long time. For many subwoofers with 300W RMS power, the dynamic power standard is often 600W or 700W. Dynamic power refers to the power output that the subwoofer can achieve in a short time. Just look at this indicator and don't be too persistent.
In addition, JL, as a major manufacturer of subwoofers, is not honest in its labeling. For example, the popular product JL F113, enthusiasts basically think this product is a 2500W RMS rated power product, but in fact, on the official page number we found such a word game-2500W RMS short-term, which shows that the RMS rated power is short. In terms of time, I can only understand that this is a way of marking premature ejaculation, which is really ridiculous.
3. Low frequency response is not as low as possible
The wider the bass sound index is the focus of many novice users when choosing a subwoofer. Now there are subwoofers everywhere claiming that they can dive to 15Hz and 10Hz. In fact, this is meaningless. Among the Blu-ray discs we watch, the recorded subwoofer channel signals are mostly 20Hz~120Hz (Dolby audio track) and 20Hz~80Hz (DTS audio track). We don't know where the signals that are played back below 20 Hz come from.
4. The subwoofer must be heavy
Of course, the premise is that there are no bricks in it. The weight of the subwoofer is composed of the unit, the cannon mount and the cabinet. The heavier the unit, the stronger the frame and the larger the magnet.