Many people want to build their own home theater, but home theater is not to buy a speaker, plus a combination of amplifiers and use it. If you want to get the best sound and picture quality, you have to consider the impedance and power of the speakers and the amplifier. , Whether the damping coefficient matches, it is necessary to master the matching method of speakers and power amplifiers.
01 Impedance matching
It means that the rated output impedance of the power amplifier should be consistent with the rated impedance of the speaker. If the rated impedance of the speaker is greater than the rated output impedance of the power amplifier, the actual output power of the power amplifier will be less than the rated output power, which will result in insufficient sound and low volume. If the rated impedance of the speaker is less than the rated output impedance of the power amplifier, the actual power will increase, which will cause distortion, and the power amplifier may be overloaded.
The rated load impedance value that the power amplifier circuit should be connected to is a basic parameter for the manufacturer to design the power amplifier. The transistor power amplifier is a low-impedance output circuit, while the tube power amplifier is a high-impedance output circuit, which has very strict requirements on the impedance value of the speaker.
02 Power matching
If the speaker impedance meets the matching requirements, and the withstand power is less than the power of the amplifier, then the driving power is sufficient and it sounds very comfortable. This is what it is often said that the reserve power of the power amplifier must be large in order to fully express all the connotations of music, especially the low frequency part of the music, which is more vivid and powerful. This is a good match.
If the rated impedance of the speaker is greater than the rated impedance of the power amplifier, although both can work safely, at this time the power amplifier is not enough to drive the power, and the loudness will be insufficient. Often the speaker has been turned on to a saturated state and the distortion is aggravated. If the power of the amplifier is greater than the power of the speaker, you will feel the low frequency is strong and powerful when listening to music, but for novices, pay attention to avoiding the speaker from being burned.
03 Damping coefficient matching
The so-called damping is an index to measure the damping of the loudspeaker by the internal resistance of the output stage of the power amplifier. If the damping coefficient is too high, the sound from the speaker will be dry and not round; if it is low, the sound will tend to stick together.
Some speakers need a high damping coefficient to control the action of the unit, but if it is equipped with a power amplifier with insufficient damping coefficient, the unit will lose control, and excess resonance and audio loss will occur; on the contrary, if a pair does not require a high damping coefficient The speaker is equipped with a high-damping power amplifier. Because the unit is controlled by high damping, the sound will become solid and the sound tail will be extremely short.
When matching power amplifiers and speakers, the main consideration is whether the above three aspects match. It will last forever if the door is right. But in general, when planning to build a home theater audio system, look at your usual usage habits. The main purpose is to watch movies and listen to music. The power amplifier can be selected according to the proportion of watching movies and listening to music.