1. The role and significance of the subwoofer
The audibility of the subwoofer to the human ear is extremely limited, but can be felt by other human senses. It’s a shocking feeling! As far as the needs of audio program sources reflected by audio and home theaters are concerned, the subwoofer only exists in a specific program source and needs to be restored. With it, the restoration of the program source can be made more solid, without it, it will give people a lack of power. , the feeling of energy. For example, in a movie theater or in reality, we can feel the shock of the power and energy when the plane takes off, but if our home theater is not equipped with subwoofers or is not properly configured, we cannot feel this shock, but also That’s all.
As far as the audio environment is concerned, in addition to listening to HIFI, whether it is watching a movie or listening to a concert, super bass is needed and should be ensured. This delineation of 0.1CH as a subwoofer channel in the two major audio reduction standards of digital home theater also shows its meaning and function, which is necessary.
But there are compromises. Because of the restoration of super bass, as a standard setter, of course, it is difficult to popularize, because the cost is huge. Without the help of other technologies, the bass playback unit should be large-diameter. In addition, driving such a large-diameter unit also requires a high-power amplifier, which will lead to a linear increase in the cost of restoring the super bass. Of course, we can also buy subwoofers with low sales prices in the market. This is actually another compromise. Technically speaking, it is a pseudo subwoofer, but from the perspective of the commodity and consumer market, this is also a market issue. need.
Second, Common sense of subwoofer in home theater
For digital home theater power amplifier, the power amplifier itself has bass management Settings, combined with the size of the speaker to adjust the cutoff frequency of the subwoofer.
Phase: Most subwoofers are designed with phase adjustment switches, and the phase adjustment of advanced subwoofers is still continuous. Phase adjustment is relatively simple, positive or negative. The correct setting should be that the sound of the subwoofer is strong and shocking. If the sound becomes ethereal after the subwoofer, then the phase switch should be changed immediately.
Connection: Professional website navigation: For home theater system, it is recommended to use low-level signal input for super bass signal. Usually faced with two choices, one is the multi-channel output from the disc player, and the other is the subwoofer output from the AV amplifier. Unless the amplifier does not have a subwoofer output terminal, we recommend that the connection is taken from the AV amplifier. This can be The subwoofer volume is controlled synchronously by the AV amplifier. If taken from a disc player, then when the system volume is changed, the volume of the subwoofer needs to be adjusted at the same time. This connection method, usually in the stereo mode, the subwoofer cannot obtain the signal, so it does not help or improve the system much. This needs attention.
If you try to take a full-band signal from a stereo signal and input it into the subwoofer, first make sure that your subwoofer has a low-pass design, otherwise, the subwoofer cannot be used. In this case, the super bass of any program can be enhanced.
Position: Strictly speaking, the subwoofer lacks directionality, so it can be placed anywhere in the listening room, but considering the environmental impact on sound transmission Huge impact, in practice, we still strongly found that moving the subwoofer has a greater impact on the restoration of the subwoofer. Generally, the subwoofer is placed one-third of the front wall, but when conditions permit, we still It is recommended that the user adjust the placement of the subwoofer to obtain the best effect.
Finally, it should be noted that the subwoofer does not always exist in the program source, so don’t make any misunderstandings when listening or debugging. Because of the habit, people will inevitably use their ears to hear whether the subwoofer is working or whether it is very shocking during debugging. In fact, it is not necessary. In order to facilitate debugging, special subwoofer signals are usually provided in the test discs on the market.
Three, home theater subwoofer purchase tips
1, bass Bigger is not better.
Beginning users buy subwoofers, many think that they are getting better and better, but this is not the case. A subwoofer with a larger unit can theoretically bring lower dive and volume, but that is theoretical. A 15-inch 2,000 yuan subwoofer is hard to beat a 12-inch 8,000 yuan subwoofer regardless of data or sense of hearing. Therefore, the more entry-level subwoofer, we recommend that you choose a small cannon, but it will be better. Because of the same price, small-sized products use more materials than large-sized ones, and the sound of smaller units is easier to control. Inexpensive large size subwoofer, I advise you not to buy it!
2, the bigger the better the better
the bigger power, and will have better driving ability and unit control ability. When choosing a subwoofer, pay attention to its standard RMS power, which indicates the rated power that the subwoofer amplifier can output stably for a long time. For many subwoofers with RMS power of 300W, the dynamic power standard is often 600W or 700W. Dynamic power refers to the power output that the subwoofer can achieve in a short period of time. Just look at this indicator, and don’t be too persistent.
In addition, as a big-name subwoofer manufacturer, JL is not honest in the labeling. For example, the popular product JL F113, enthusiasts basically think that this product is a 2500W RMS rated power product, but in fact we found such a word game on the official page number – 2500W RMS short-term, which means that the RMS rated power is short-term. In terms of time, I can only understand that this is a way of marking premature ejaculation, which is ridiculous.
3, the low frequency response is not as low as possible
The wider bass sound index is a lot of small White users choose the focus of the subwoofer. Now there are subwoofers everywhere claiming that they can dive to 15Hz, 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 those signals that play back below 20Hz are coming from.
4The bigger the box is, the better.
Some people buy subwoofers thinking that bigger is better. There is no basis! The size of the box is related to the volume, but there is no absolute relationship. If a large box without sound-absorbing cotton and a small box with a regular subwoofer have a lower effective volume than the subwoofer, the former is less effective than the latter.
5, the subwoofer must be heavy.
Of course, the premise is that it is not a brick. The weight of the subwoofer consists of the unit, the amplifier and the cabinet. The heavier the unit, the stronger the pot frame and the bigger the magnet.
The heavier the box, the higher the density of the board. And the heavier the blasting plate, the larger the ring cow is. However, there are also irregular products that play bricks in the subwoofer box, so it is very important to buy a regular brand.
