How does a subwoofer box affect the sound?
Content
In car audio, there are many options for acoustic design boxes. Therefore, many beginners do not know what is best to choose. The most popular types of boxes for a subwoofer are a closed box and a phase inverter.
And there are also such designs as bandpass, quarter-wave resonator, free-air and others, but when building systems they are used extremely rarely for various reasons. It is up to the owner of the speaker to decide which subwoofer box to choose based on sound requirements and experience.
We advise you to pay attention to the article from which material it is better to make a subwoofer box. We have clearly demonstrated how the rigidity of the box affects the quality and volume of the bass.
Closed box
This type of design is the simplest. A closed box for a subwoofer is easy to calculate and assemble. Its design is a box of several walls, most often of 6.
ZY advantages:
- Simple calculation;
- Easy assembly;
- Small displacement of the finished box, and therefore compactness;
- Good impulsive characteristics;
- Fast and clear bass. Plays club tracks well.
The disadvantage of a closed box is only one, but it is sometimes decisive. This type of design has a very low level of efficiency relative to other boxes. A closed box is not suitable for those who want high sound pressure.
However, it is suitable for fans of rock, club music, jazz and the like. If a person wants bass, but needs space in the trunk, then a closed box is ideal. A closed box will play poorly if the wrong volume is selected. What volume of the box is needed for this type of design has long been decided by experienced people in car audio through calculations and experiments. Volume selection will depend on the size of the subwoofer.
Most often there are speakers of these sizes: 6, 8, 10, 12, 15, 18 inches. But you can also find speakers of other sizes, as a rule, they are used very rarely in installations. Subwoofers with a diameter of 6 inches are produced by several companies and are also rare in installations. Most people choose speakers with a diameter of 8-18 inches. Some people give the diameter of the subwoofer in centimeters, which is not entirely correct. In professional car audio, it is customary to express dimensions in inches.
Recommended volume for subwoofer closed box:
- 8-inch subwoofer (20 cm) requires 8-12 liters of net volume,
- for 10 inch (25 cm) 13-23 liters net volume,
- for 12-inch (30 cm) 24-37 liters of net volume,
- for 15" (38 cm) 38-57-liter net volume
- and for an 18-inch (46 cm) one, 58-80 liters will be required.
The volume is given approximately, since for each speaker you need to choose a certain volume based on its characteristics. The setting of a closed box will depend on its volume. The larger the volume of the box, the lower the tuning frequency of the box, the bass will be softer. The smaller the volume of the box, the higher the frequency of the box, the bass will be clearer and faster. Do not increase or decrease the volume too much, as this is fraught with consequences. When calculating the box, adhere to the volume that was decreed above. If there is a search for volume, then the bass will turn out to be vague, fuzzy. If the volume is not enough, then the bass will be very fast and “hammer” on the ears in the worst sense of the word.
A lot depends on the box settings, but no less important point is the “Radio Setup”.
Phase inverter
This type of design is quite difficult to calculate and build. Its design is significantly different from the closed box. However, it has advantages, namely:
- High level of efficiency. The phase inverter will reproduce low frequencies much louder than a closed box;
- Simple hull calculation;
- Reconfiguration if necessary. This is especially important for beginners;
- Good speaker cooling.
Also, the phase inverter also has disadvantages, the number of which is greater than that of the WL. So the cons:
- PHI is louder than WL, but the bass here is no longer so clear and fast;
- The dimensions of the FI box are much larger compared to the ZYa;
- Large capacity. Because of this, the finished box will take up more space in the trunk.
Based on the advantages and disadvantages, you can understand where the PHI boxes are used. Most often they are used in installations where loud and pronounced bass is needed. The phase inverter is suitable for listeners of any rap, electronic and club music. And also it is suitable for those who do not need free space in the trunk, as the box will occupy almost the entire space.
The FI box will help you get more bass than in the WL from a small diameter speaker. However, this will require much more space.
What volume of the box is required for a phase inverter?
- for a subwoofer with a diameter of 8 inches (20 cm), you will need 20-33 liters of net volume;
- for a 10-inch speaker (25 cm) - 34-46 liters,
- for a 12-inch (30 cm) - 47-78 liters,
- for a 15-inch (38 cm) - 79-120 liters
- and for an 18-inch subwoofer (46 cm) you need 120-170 liters.
As in the case of ZYa, inaccurate numbers are given here. However, in the FI case, you can “play” with the volume and take a value less than the recommended ones, finding out at what volume the subwoofer plays better. But do not increase or shrink the volume too much, this can lead to a loss of power and speaker failure. It is best to rely on the recommendations of the subwoofer manufacturer.
What determines the setting of the FI box
The larger the volume of the box, the lower the tuning frequency will be, the bass speed will decrease. If you need a higher frequency, then the volume must be reduced. If your amplifier power rating exceeds the speaker rating, then it is recommended to make the volume smaller. This is necessary in order to distribute the load on the speaker and prevent it from exceeding the stroke. If the amplifier is weaker than the speaker, then we recommend making the volume of the box a little larger. This compensates for the volume due to the lack of power.
The area of the port should also depend on the volume. The average speaker port area values are as follows:
for an 8-inch subwoofer, 60-115 sq.cm will be required,
for a 10-inch - 100-160 sq. cm,
for a 12-inch - 140-270 sq. cm,
for a 15-inch - 240-420 sq. cm,
for 18-inch - 360-580 sq. cm.
The length of the port also affects the tuning frequency of the subwoofer box, the longer the port, the lower the box setting, the shorter the port, respectively, the tuning frequency is higher. When calculating a box for a subwoofer, first of all, you need to familiarize yourself with the characteristics of the speaker and the recommended box parameters. In some cases, the manufacturer recommends completely different box parameters than those given in the article. The speaker may have non-standard characteristics, because of which it will require a specific box. Such a subwoofer is most often found in Kicker and DD manufacturing companies. However, other manufacturers also have such speakers, but in much smaller quantities.
Volumes are approximate, from and to. It will differ depending on the speaker, but as a rule they will be in the same plug ... For example, for a 12 inch subwoofer, this is 47-78 liters and the port will be from 140 to 270 square meters. see, and how to calculate the volume in more detail, we will learn all this in subsequent articles. We hope that this article answered your question, if you have any comments or suggestions, you can leave your comment below.
The information that you learned is perfect for those who want to learn how to count the boxes on their own.
Conclusion
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