Кроссовер первого порядка калькулятор

DIY Audio & Video

An APC (All-Pass Crossover) circuit is designed to create a flat voltage output. This 3-Way Crossover Designer is more than just two combined 2-Way Crossovers. The parameters are slightly different to account for 3 drivers. The parameters can only be calculated when the 2 crossover points are 3.0 or 3.4 octaves apart.

Note: For this calculator, bandpass refers to the midrange driver where both the low pass and high pass filters are applied. For more information on crossovers, see the 2-Way Crossover Help, the Crossover Tutorial & the Crossover FAQ.

To use this calculator, enter the resistance of each driver, one of the crossover points, the frequency spread, and the crossover type. The second crossover frequency will be automatically calculated. The bandpass gain (the db gain for the midrange driver) is also automatically calculated. This gain will vary with the crossover spread and type.

A 2+ bandpass gain is significant, and it will make the mids sound louder than the rest of the speaker system. If the sensitivity of the midrange speaker is 2db lower than the other drivers, then this will actually solve a problem for you. Otherwise, you may want to use a Parallel Notch Filter to lower the output of the midrange driver.

Note that some crossovers can produce phase shift problems. A second order crossover will shift the phase of each speaker 90 degrees, so that both speakers are 180 degrees out of phase. This means that at the crossover frequency, the two drivers will be moving in opposite directions at the same time. They will cancel each other out and produce a 30db dip in the frequency response at the crossover point. Reversing polarity of one (but not both) of the speakers will limit this dip to +- 3db. Each 3-way APC crossover is labeled as reverse or normal polarity for the bandpass speaker. For the reverse polarity crossover, the + and — connections on the midrange (bandpass) speaker are reversed. The reversing in polarity prevents phase shift problems.

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Crossover Calculator:
LR2, Bessel, Butterworth & Cheybyscheff

It is very helpfull if you are able to measure the frequency response of the drivers to choose the best crossover frequency.

If you choose a crossover point in a range where the driver’s frequency response is changing rapidly off-axis, the off-axis response will have large response anomalies.
Large variations in the off-axis response degrade the power response the listener perceives. Reflected and reverberant response will be significantly different from the on-axis response, and generally devalue the overall quality.

Selecting the best slope is important, both to protect the tweeter (in particular), and to ensure that the drivers are all operated within their optimum frequency and power handling ranges.

A 6dB/octave (first-order) filter has the most predictable response, and is affected less by impedance variations than higher orders. On the negative side, the loudspeaker drivers will be producing sound at frequencies that are very likely outside their upper or lower limits.

12dB/octave (second-order) filters are better at keeping unwanted frequencies out of the individual speakers, but are more complex, and are affected by impedance variations to a much greater degree. The tolerance of the components used will also have a greater effect. The capacitance used must remain predictable and constant over time and power, which specifically excludes the use of bipolar electrolytics.

A 18dB/octave (third-order) filter requires closer tolerances than a second order, and is again even more susceptible to any impedance variations than the 12dB filter.

24dB/octave (fourth-order) filters increases the complexity and tolerance requirements even further — a point must be reached where the requirements versus the complexity and sensitivity will balance out.

How does it work?

For this example i use a second order (12dB) Highpass crossover network for 1 kHz.

• Crossover frequency: 1 kHz ( Linkwitz-Riley Crossover )
• Driver impedance: 10 ohm
• Inductor: 3.18 mH
• Capacitor: 8 uF

Now, the capacitor is in series with the driver and the inductor is parallel with the driver.

The capacitor and the inductor together with driver are a voltage divider.

Calculation of this divider:
6.66 ohm / (6.66 ohm + 20 ohm) = 0.25

That means a input-voltage of 1 volt will be a output-voltage of 1 * 0.25 = 0.25 volt

And how much dB is that?
20 * log(0.25) = -12dB

Brief explanation

Second order Linkwitz-Riley ( LR2 )

(The Linkwitz-Riley filter has a crossover frequency where the output of each filter is 6dB down, and this has the advantage of a zero rise in output at the crossover frequency.)
Second-order Linkwitz-Riley crossovers (LR2) have a 12 dB/octave (40 dB/decade) slope. They can be realized by cascading two one-pole filters, or using a Sallen Key filter topology with a Q value of 0.5. There is a 180° phase difference between the lowpass and highpass output of the filter, which can be corrected by inverting one signal. In loudspeakers this is usually done by reversing the polarity of one driver if the crossover is passive.

Bessel filter

( Maximally flat phase, Fastest settling time, Q: 0.5 to 0.7 (typ) )
A Bessel filter is a type of linear filter with a maximally flat group delay (maximally linear phase response). Bessel filters are often used in audio crossover systems. Analog Bessel filters are characterized by almost constant group delay across the entire passband, thus preserving the wave shape of filtered signals in the passband.

Butterworth filter

( Maximally flat amplitude, Q: 0.707 )
The Butterworth filter is a type of signal processing filter designed to have as flat a frequency response as possible in the passband. It is also referred to as a maximally flat magnitude filter.

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Crossover Calculator

The Crossover Calculator is a useful tool for creating great sound speakers. Using the Crossover Calculator, figure out how many capacitors and inductors you’ll need to make a passive crossover for your speakers. Simply fill in the blanks in the tool and hit the calculate button to get results in a flash.

Crossover Calculator: Would you like some help deciding on the optimum crossover design for your speakers? If that’s the case, you’ve come to the right place for information on passive crossover design. Learn why you need more than one speaker to get better sound and what electronic components you’ll need to send the most appropriate frequencies to the speaker. Learn about numerous circuits that maintain the impedance of speakers when frequency varies (Zobel), as well as another model that lowers the volume (L-Pad).

Why is it that having multiple speakers is preferable to having just one?

Are you confused as to why you require additional speakers to improve the sound quality? The usual complaint about single speakers is that they don’t sound good at all frequencies. They have a low volume and poor bass response, as well as low-frequency sound distortions. Making the speaker larger will address this problem. However, low volume at high frequencies would ensue if this were done. We seek the same sound volume across a wide variety of frequencies when designing a hi-fi speaker. More speakers in the speaker unit can help you solve this problem. The tweeter is a speaker that produces high frequencies, whereas the woofer creates low frequencies. In a three-speaker setup, you’ll have a mid-range speaker that bridges the gap between high-quality tweeters and low-quality woofers. When connected to an amplifier, these multiple speaker setups have an issue as well. Because the speaker cable carries all frequencies, the woofer receives high frequencies while the tweeter receives low frequencies. When a powerful signal is received at the wrong frequency, frequency mismatch causes sound distortion and can potentially harm the speakers.

Passive Crossover Design

Splitting the signals flowing from the amplifier according to the sound frequency is one solution for overcoming the problem of sound distortion. The appropriate combination of tweeters and woofers will allow the speaker to receive a wide range of frequencies. When two speakers are used, the design is referred to as a 2-Way Passive Crossover, and when three drivers are used, the design is referred to as a 3-Way Passive Crossover. It’s called passive since it doesn’t require any additional power from the speaker. You can also utilise an active cross design to solve the sound distortion problem, in which the signal is broken up before it is amplified. Both low-pass and high-pass crossover filters are used in 2-way cross over designs. A low pass filter permits frequencies below a specific threshold, while a high pass filter allows frequencies over that threshold. The frequency at which low-pass begins to diminish and high-pass begins to increase the signal amplitude are known as the crossover frequency. A bandpass filter is added to a 3-way crossover system, which chooses midrange frequencies for midrange speakers.

Filter Type and Order

The crossover sequence, as well as the filter characteristic, can both be customised. A 1st Order Crossover Design is the simplest of all the orders, with only one capacitor and one inductor. It has a slope of 6dB/Octave, which is the lowest slope conceivable. You can find out how much attention the filter is paying when the frequency changes by looking at the slope value. In this instance, there is a minor power loss. However, there is still a potential that incorrect impulses will enter the speaker, causing harm. Further sections will provide you with an overview of some of the higher-level filters as well as their characteristics. For more concepts check out physicscalculatorpro.com to get quick answers by using this free tool.

Crossover Design of the Second Order

• It features a slope of 12dB/Octave, which provides for additional absorption of undesirable signals.
• It is the most widely used design because it has the fewest components.
• Sufficient Protection for High-Frequency Tweeter-Driver.
• Butterworth, Bessel, Linkwitz, and Chebyshev.

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Кроссовер первого порядка калькулятор

Higher Order Analog Butterworth Filter Designs, a Tutorial

1. Make sure you have Java turned on in your browser.
2. Enter high and low pass speaker impedances.
3. Enter desired crossover frequency.
4. On the second-order crossover calculator you must select type of crossover.
5. Click on the «calculate» button to get the answers.

1. First Order Crossover (6db/octave).
2. Second Order Crossover (12db/octave).
3. Third Order Crossover (18db/octave).
4. Fourth Order Crossover (24db/octave).
5. Zobel Circuit (Impedance Stabilization).
6. L-pad Circuit (Speaker Attenuation).

First Order (6db/octave) Two-Way Crossover

Second Order (12db/octave) Two-Way Crossover

• Linkwitz-Riley crossovers match attenuation slopes so that system response is flat at crossover point.
• Butterworth crossovers yield to a peak at the crossover frequency.
• Bessel crossovers have a frequency response between Linkwitz-Riley and Butterworth crossovers.
• The phase shift on a second-order crossover is 180 degrees (reversed polarity).

Third Order (18db/octave) Two-Way Crossover

Fourth order (24dB/octave) Two-Way Crossover

Zobel Circuit (Impedance Stabilization)

• Even though speakers are rated at a certain «resistance» (i.e. 4 Ohms), the actual impedance varies with frequency (speakers have inductance). To compensate for the non-linearity of speakers (on mainly subwoofers), Zobel circuits are used.
• Re is the DC resistance of the woofer (can be measured with an ohmmeter)
• Le (or Lces) is the electrical inductive equivalent of the driver.

• An L-pad circuit will attenuate a speaker.
• L-pads keep the load «seen» by the amplifier constant, affecting only the power delivered to the speaker. The power delivered by the amplifier remains constant.
• Since L-pads are made from resistors, it does not induce any phase shifts, or affect frequency response.

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