Important crossover design of speakers

Important crossover design of speakers

When we disassemble the speaker, in addition to the material used by the manufacturer for tuning, there will be a circuit board sandwiched between the output terminal and the sound unit, and this circuit board is the crossover. Its function is equivalent to the "brain" in the speaker, which sends analog signals into different parts of the corresponding sound unit, such as high, medium and low sound, and then achieves better playback effect.

Speaker crossover

Crossover are commonly used in high and low-pitched units. Perhaps in a speaker with a mezzo unit, a multi-unit speaker without a crossover can't play back the dynamics of different frequencies. In addition, the variety and quality of the crossover also affect whether the speaker can play back better dynamic performance.

Speaker crossover

About the crossover that have to know the general knowledge, by "Yihe sound" for us to introduce in detail.

What is the use of the crossover?

Whether the tweeter or the bass, their own frequency response curves are not flat, tweeters and bass loudspeakers will be attenuated at both ends, so that the upper attenuation part of the low-frequency response may overlap or even interweave with the lower attenuation part of the high-frequency response, forming a frequency overlap and can not form a flat. Curve, so that the dynamics that come out will not be good sound quality.

Speaker crossover

Assuming that it is not enough to simply dock them together, the effect of the crossover is to act as a combination of these frequencies between the speakers to achieve better results. The crossover processes the music signal of the amplifier through the filter wave source to let the specific frequency signal of each unit pass. In short, the original signal is cut into several frequency bands, and the crossover selects the most suitable frequency band for the corresponding unit to play and distributes it to complete the cooperative operation of multiple speakers.

Speaker crossover

The demanding of crossover is chosen by the speaker's own planning. Double crossover is cut into two segments, while triple crossover is cut into three segments. This is what we often call "two paths" and "three paths". According to the operation principle of crossover, it has a variety of ways to complete, it also divides into different types of planning, but we often see Active crossover and electronic crossover two categories, which is often heard of the concept.

Speaker crossover

Active crossover centered on electronic parts

Active crossover is planned after the power expander, the first choice is capacitor and inductance components, so it is also known as inductance crossover. Because inductance and capacitance have filtering effect, through inductance and capacitance can be completed low-pass and high-pass, after all, to achieve the purpose of cutting frequency. This kind of crossover is set inside the speaker. Through the LC filter network, the audio signal output by the power amplifier is divided into high, medium and low dividends and then sent to each sound unit.

Speaker crossover

The simplest Active crossover is the capacitive crossover, which is the way to complete the crossover by connecting a capacitor in series behind the tenor unit. Slightly cluttered, it is possible to use capacitors and inductances in each path to achieve more precise frequency cutting. However, Active crossover equipment is still very simple, active and passive speakers can be applied. The power crossover also has attenuation phenomenon in the frequency band after frequency cut, and the slope of attenuation curve is generally related to the number of filtering.

Speaker crossover

But the shortcomings of Active crossover are also obvious, it consumes power itself, will appear audio Valley and cross-distortion. The parameters of other Active crossovers are directly related to the impedance of the loudspeaker unit itself, because the impedance of the unit is a function of frequency and violates the nominal value greatly, so the fault is very large, which is not conducive to tuning. Satisfactory experience and technology may be required to complete the Active crossover.

Speaker crossover

Electronic crossover using audio signal operation

Unlike the Active crossover, the electronic crossover is located before the power expander. The electronic crossover divides the weak audio signal into different frequencies, then expands the signal of each frequency band with its own power amplifier and transmits it to the unit of the speaker respectively to complete the dividing effect. For example, if two-way (two-way) speakers use electronic crossover, the two-way signal will be divided into four channels, so the back-end amplifier needs four channels to tune the output.

Speaker crossover

Electronic crossover has obvious advantages in technology. First of all, it does not have power loss like Active crossover. Its current is small enough to be completed by small power electronic active filter. Its power loss is not obvious or even negligible. The electronic crossover's speaker units will have less disturbance, less signal loss, and a slightly better sound quality. Of course, its tuning is more intuitive and convenient.

Speaker crossover

Of course, the electronic crossover also exists shortboard, because of the operation principle, each channel of the electronic crossover needs to use an independent power amplifier, the cost is high, the circuit structure planning will be more messy, but the power crossover selection is now relatively high-priced brass, it is still a cost advantage. And because electronic crossovers are generally integrated with power amplifier systems, electronic crossovers are less playable for DIY speakers.

Speaker crossover

Conclusion: With the crossover, multi-unit speakers can be tuned to playback clearly and accurately. And the quality of crossover, just on behalf of the manufacturers'own technical strength, only experienced rich, technological manufacturers to modulate a high-quality crossover. There is no doubt that the speakers on the back are not the crossover.