It is selected according to the frequency range of the tweeter and the frequency range of the woofer. When the tweeter unit is combined, in order to make them work individually; the tweeter only sends out the treble part, and the woofer unit only sends out the bass part, so add A crossover, select the crossover frequency, so that their crossover frequency becomes relatively flat, so that the sound becomes more perfect and beautiful when replayed.
If you use a crossover, you can directly add the sound of all frequencies to all the speakers. The woofer can withstand the treble, but the tweeter cannot withstand the bass. If the sound is slightly louder, it will burn the treble directly. The principle is to divide the input full-range sound into three frequencies: treble, midrange and bass, and then connect the speakers to each, so that the sound will be pleasant. The characteristics of the high, middle and bass speakers are different. If all the sounds are input to Playing each speaker will inevitably cause adverse effects, resulting in poor sound quality. Therefore, a crossover is needed to divide the sound into several frequency bands and output to the speakers of each frequency band for playback. This brings about a problem that the frequency bands are connected. If the connection cannot be made, a part of the sound will not be heard, which will cause distortion.
How to match the frequency divider and the speaker
1. Rated impedance. Common rated impedances of speakers are 4 ohms, 6 ohms, 8 ohms, 16 ohms, etc. Since the current speakers are driven by transistors or integrated circuit power amplifiers, and these types of amplifiers generally do not use output transformers, the impedance of the connected speakers is mostly in the range of 4-16 ohms, and should be selected according to the requirements of the power amplifier during use. The impedance of the speaker.
2. Effective frequency range. The wider the sound pressure frequency range of the speaker, the better the frequency characteristics. The effective frequency range of speakers is strictly regulated in the International Electrotechnical Commission standards. Although some manufacturers have marked the frequency response range of speakers, they have not marked the effective range. For example, a pair of speakers indicate a frequency response range of 20Hz-20kHz, and another pair of speakers indicate a frequency response range of 30Hz-17kHz±3dB. Compared with the latter, it seems that the frequency response of the latter is not as wide as the former, but in fact, the frequency response curve of the latter pair of speakers It is indicated that it only changes within ±3dB, so the latter is better than the former.
3. Frequency divider. Generally speaking, the performance of three-way speakers should be better than two-way speakers. Because the three-way frequency adds a mid-range speaker unit, the mid-range can be made more mellow. Moreover, the power shared by the three speakers is reduced, so the entire speaker can bear more power and output a greater volume. Of course, the three-way speaker adds a midrange unit and a crossover, and its price is more expensive than the two-way speaker of the same grade.
4. Sensitivity. Generally speaking, a speaker with a sensitivity of 90dB is sufficient to meet the needs of home audio.
5. The caliber of the speaker. The diameter of the woofer is generally 20-38cm, and there are also large diameters of 60cm or 72cm; the diameter of the tweeter is generally 2-6cm, and some are larger than 9cm. For woofers, the bigger the caliber, the better. Because the larger the caliber, the easier it is to deform the paper cone when it vibrates, resulting in segmented vibration, which causes distortion.
Sixth, the net weight of the speaker. Generally speaking, the heavier the speaker, the better the quality. Because the heavier the speaker, the larger the magnet or the thicker the sheet material used in the speaker, both of which will make the sound quality better.
Match requirementsBuy speakers sold by more regular manufacturers should also be equipped with a horn performance index parameter table, if not, you can refer to the usual reference: the frequency divider of 4 inches or less selects 4000Hz, 6.5 inches selects 3500, 8 inches selects 3000, and 10 inches or more selects 2200Hz.
The impedance of the high and low speakers should be the same and the power should be close. The positive and negative poles are connected correctly.
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