The speaker is basically composed of three parts: the speaker, the crossover, and the cabinet. According to the number of speakers, it is divided into two units, three units...
There is also a combination of a tweeter and a woofer, called a coaxial unit, which is a unit from the outside and actually belongs to two units.
As the name implies, the frequency divider divides the frequency band [20--20000 Hz] of the audible sound into several frequency bands and sends them to the corresponding speaker unit. According to the division of the frequency band, it is divided into two parts: high and low. The two-way frequency is divided into high, medium and low three, called three-way, and so on.
The box body is generally made of logs or MDF, and is divided into closed boxes according to the structure of the box [no phase inverting holes, air inside and outside of the box body], and phase inverting box [with inverted phase holes]. There are also some box structures that are not commonly seen: labyrinth, exponential, negative resistance, horn, etc.
According to the scope of use of the speaker is divided into: professional box [for performance, hall, hall, field, hall sound reinforcement]
Monitor box [professional monitor for various recording agencies] civilian box.
According to the way the speakers are placed, they are divided into bookshelf boxes and floor-standing boxes. The bookshelf boxes are mostly two-unit, two-way structure, and are used in rooms within 20 square meters. The floor box is mostly multi-unit, multi-frequency structure. More than 20 square meters.
Speaker performance indicators:
The general speakers are marked with the most common of his many application parameters:
Power: Generally measured by W or VA, the common nominal power [rated power, undistorted power] refers to the maximum input power under the condition that the nonlinear distortion does not exceed the standard range of the speaker . He is the normal working power of the speaker , and will not be damaged if it is working continuously for a long time.
Sensitivity: He is defined as the sound pressure generated at a distance of one meter from the reference point when a pink noise voltage of 1 watt is applied to the speaker . Expressed in decibels [db]. The higher the sensitivity of the speaker , the louder it is at the same drive power. This makes sensitivity important when using a low-power amplifier.
Impedance: It refers to the audio signal applied to the input terminal of the speaker, the speaker exhibits a pure resistance. Commonly there are 4 Euros, 8 Euros, and there are also 3 Euros and 5 Euro systems abroad. Pay attention to match the output impedance of the amplifier. In particular, the amplifier is especially important for matching the impedance of the speaker .
Frequency Range:
Its definition is not easy to say in a few words. Generally speaking, it refers to the frequency playback range when the speaker drops at a negative 3 db level in the audio range. Naturally, the wider the better, the current HI-FI speaker can achieve 20,000HZ or even 30000HZ playback at the high frequency end. It is not a problem. Due to the limitation of the speaker diameter and the volume of the cabinet, the low frequency band is 20HZ. Not easy, the low frequency band of the general bookshelf speakers is even worse.
I already know something about the speakers . It's really simple, but it's not easy to do it. For beginners, after mastering a certain speaker knowledge base, it is not difficult to make a pair of entry-level HI-FI speakers . In particular, some merchants have introduced a number of speaker kits. You only need to carefully install them according to the production drawings. The success rate is extremely high, and since these kits have been carefully designed and matched by the manufacturers, the sound quality and effects are guaranteed. And its cost is only one-half to one-quarter of the finished product. Compared with the imported speakers with a set of units, the author's speakers made with the gentleman's 8545K unit are evaluated by many senior enthusiasts. The sound is never under the foreign goods, and the cost is only 3,000 yuan. One of the points.
Don't make a speaker , make a few units and crossovers, buy a finished box and go to the top. The speakers made in this way are definitely not good. And now there are too many counterfeit and counterfeit products on the market, and the quality is not guaranteed. The safer approach is to mail out kits from some of the more reputable sales units. If your carpentry skills are good, it is perfectly possible to build the cabinet according to the recommended drawings, or find the carpentry master to do it, as long as the cabinet volume and the recommended volume of the woofer match.
Little knowledge of hanging sound:
The suspension sound spreads on average even on the flat ground. We know that at this time: sound pressure = 20LOg (reference distance / distance), ie SPL = 20LOg (Dref / D)
If it is twice as far as the speaker , the sound pressure will be reduced by 6db (anti-square law), because SPL=20LOg(1/2)=20LOg0.5=20*(-0.301)=-6db
Hanging speakers have its advantages, but if you are going to hang a speaker , please pay attention to hiring a professional consultant, because this is a matter of life. Note that the suspension system should calculate the endurance in the weakest connection. When installing the suspension speaker system, you must be aware of the strength of the suspension components you are using. During the installation process, you should pay attention to some specific problems, such as the force distribution on the sling. At this time, the internal angle sine value = Load Angle Efficiency, keep the inner angle minimum and not too flat, which will reduce the sling's bearing capacity.
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