Parallel connection of acoustics. Parallel and series connection of speakers. Methods for assembling a speaker system

If you are building a loud front with a large number of speakers, then you will have to connect them together in order to connect two or more speakers to one amplifier channel. Of course, no one puts one din per channel, it’s just expensive.

If, for example, you install 4 pairs of speakers, of course it is better to connect them in pairs, it will be more reasonable, and the power will be higher, and you will need one 4-channel amplifier. As long as the total resistance of the dins connected in parallel to one channel is not less than the tolerance (for example, 2 Ohms or 1 Ohm), everything is fine. But when they want more speakers, people start combining switching methods. For example, four 4-ohm speakers are switched in series in pairs and the pairs are connected in parallel. The total resistance is 4 Ohms, 4 speakers are connected per channel. Everything seems to be fine. And to make things really good, another 4-ohm speaker is switched in parallel, then the total resistance is 2 ohms and 5 speakers are connected to each channel.
There are also more witty combinations. For example, three speakers are placed on a channel. One 8 ohm, and two 4 ohm. The four-ohm ones are connected in series and an eight-ohm one is connected to them in parallel. The sum is again 4 Ohms, from a mathematical point of view everything is fine.

But there are nuances. The trouble is that the power between the speakers is not distributed evenly. Some are overloaded, others are resting.
To figure out what's what here, you need a little math.
Let's say that we have two speakers with resistance R 1 and R 2 and they are both connected to the same amplifier channel in series or parallel. The amplifier power P will be distributed between the speakers:

P=P 1 +P 2

where P 1 and P 2 are the powers that “arrive” on the dynes.
What is the ratio of these powers? How different can they be?

Serial connection

If the speakers are connected in series, then a total current flows through them. The power dissipated by them will be I 2 R 1 and I 2 R 2, respectively

P=I 2 R 1 +I 2 R 2

where I is the total current flowing through both speakers.

From the last equation it is clearly clear that the power will be dissipated more on the dyne that has greater resistance. That is, if we connect an 8-ohm and a 4-ohm speaker in series, the 8-ohm speaker will be loaded more. This sounds strange to many, but it is true. Therefore, I would categorically not recommend connecting speakers with different resistances in series. In fact, only one will work.

What happens if the speakers have the same impedance? In theory, the power should be distributed evenly. But there is one thing that is almost never written about - the reactive component of the total resistance. The impedance is not constant, it depends on the frequency of the signal supplied to the speaker coil. As the frequency increases, the impedance increases, and the inductance of the voice coil is to blame. Everyone knows this.
But there is another component of impedance that is very important and never mentioned. The fact is that a speaker is not just a coil with inductance, it also moves in a magnetic field. Essentially, any speaker of a popular design is a reciprocating electrical machine. Electric motor. Like almost all electric machines, it is reversible. This means that during operation the speaker generates some EMF which is expressed in an increase in impedance - total resistance. The greater the amplitude of the oscillations, the greater the total resistance will be. The increase in impedance is not large over almost the entire audio range and does not have a noticeable effect. Apparently that's why they don't remember her. But near the speaker's natural resonant frequency, the magnitude of the back-EMF is so large that the associated increase in impedance can be 10-20 times greater than all other components of the impedance.

Look at the picture. It shows the real impedance characteristic of the Oris GR-654 speaker. At the resonant frequency its total impedance is 48 ohms. This is simply a colossal amount. It is more than 10 times the total resistance over the operating range.

Why did we talk about this phenomenon at all?
The fact is that when you buy a pair of speakers, they are the same only formally. In fact, the speakers, even taken out of the same box, are slightly different. In some places the coils are a couple of turns larger, in others the movement is a little harder or softer, etc. In any case, the dynamics will oscillate with different amplitudes. Then one will have more resistance than the other. The power will not be distributed evenly. And if the speakers operate near resonance, and this is almost always the case, the situation will not be pleasant at all. The speaker with more resistance will be loaded more. A little. The vibration amplitude of its diffuser will be slightly larger. Accordingly, the resistance will increase even more, which will further increase the imbalance in power, which will increase the resistance even more, and so on. But we remember that near resonance the resistance can increase 10 times. One of the speakers will take care of everything. This results in a classic version of a system with positive feedback. One of the speakers will quickly overload, while the other will rest. There can be no talk of normal sound. You will have to “cut” the dynes at frequencies significantly higher than the resonance frequency.
In general, I would not recommend connecting speakers in series. With midrange drivers and tweeters this still works out somehow, but with subwoofers it’s a problem. They always operate in an area of strong impedance unevenness. Therefore, if two speakers are connected in series (namely speakers, not coils of one speaker, this is important), only one works and is quickly overloaded, and the second dangles like a passive radiator. I have never seen a normally working subwoofer with two speakers connected in series. Even by eye it is clear that their diffusers do not vibrate in phase. This is often attributed to the wrong case, although it has absolutely nothing to do with it.

The attached video clearly shows how two Oris LW-D2.12 speakers connected in series work completely at odds. Not in antiphase, as it might seem at first glance, but out of tune. This is due to the fact that with large oscillation amplitudes, a large imbalance in the load between the speakers develops.

Parallel connection.

If the speakers are connected in parallel, the currents flow through them are different, but the signal across them is exactly the same. Therefore, the power distribution equation can be written in another form:

P=U 2 /R 1 +U 2 /R 2

where U is the signal supplied to the speakers.

This equation shows that the lower the speaker impedance, the more power it dissipates. If you connect an 8-ohm and a 4-ohm speaker in parallel, the 4-ohm speaker will be loaded mostly. The other will be in a relaxed state.

If we connect speakers with the same impedance, the power distribution between them will be completely different. Here there will be a classical system with negative feedback. That is, the greater the resistance of the speaker, the less power will be dissipated on it. The system will operate absolutely stably, the power will be distributed almost equally. You can even turn on speakers of different sizes from different manufacturers, and there will be no imbalance.
In general, parallel connection is the best option for any speakers. The only one for subs.

Should I combine parallel and serial connections?

I would not recommend it, especially if speakers with different resistances are connected. For example, if you connect two 4-ohm speakers in series and another 8-ohm speaker connected to them, the power will be distributed extremely unevenly across them. At best, 50% for 8-ohm, and 25% for 4-ohm.

In principle, it is possible to connect speakers in series/parallel with the same resistance, but it is worth remembering that there can be a large imbalance in power between those connected in series.

How to connect speakers?

Definitely parallel, and everything will be fine. Speakers of any type and in any quantity should be connected in parallel, if of course it makes sense. Of course, the total resistance must be within the tolerance of the amplifier. It is worth connecting more than two speakers per channel only in this case. if you have a really powerful amplifier, 500 or more watts per channel. No matter how you connect the speakers, the amplifier's power will be distributed across them. And if your amplifier has 100-150 W, you shouldn’t expect much output. Two dynes in parallel - that's all it will be. And the output will be noticeably higher, and you will get everything out of the amplifier.

Options for load resistance when connecting speakers to an amplifier

To connect, for example, four speakers, you need to use one four-channel or two two-channel amplifiers for them. However, sometimes it is not possible to install another amplifier, and it is necessary to increase the number of speakers. For example, it may be necessary to connect four (2 per channel) or eight speakers (4 per channel) to the amplifier. In such cases, three connection methods are used: serial, parallel and combined (a mixture of the first two). The most important thing is to find out what the minimum allowable load resistance of the amplifier is and, based on this, choose the connection method.
Daisy chaining of speakers

In daisy chaining, the speakers are connected in series, one after the other. It is very important to phase the speakers correctly, connecting the plus of one speaker to the minus of the other. When connected in series, the total resistance increases and the output power decreases. This method can be used to reduce the output power of a channel that is supporting the sound of others - such as the rear or center channels. It is better to connect no more than two speakers in series, since more speakers will greatly reduce the output power. You cannot connect speakers with different impedances, for example, four- and eight-ohm, since in this case each of them will have a different volume. Only exactly identical speakers can be connected in series, because different speakers can also have different resistances in the 0.5 Ohm range.
When connected in series, the speaker impedance is calculated using the formula:
Where R is the resistance that we get as a result of such a connection, and R1 and R2 are the resistance of speakers 1 and 2. The resistance of more speakers is calculated similarly: R = R1 + R2 + R3 + ... + Rn, i.e. resistances are summed up.
The reduction in power due to increased load is calculated using the formula:
P = Preal (Rreal/Rcurrent),
Where P is the power at a changed load, Preal is the rated power of the amplifier at standard resistance, Rreal is the load resistance at which the real power of the amplifier was measured (rated load resistance), Rcurrent is the total resistance of the speakers that we obtained. This formula can be used for any of the three types of connection described, and with its help it is easy to calculate the increase or decrease in amplifier power due to non-standard load.
Parallel connection of speakers

By connecting speakers in parallel, the output power increases and the resistance decreases. When connecting two four-ohm speakers in this way, their combined impedance becomes 2 ohms, and you need to know whether the amplifier can handle such a low load. Much more often you come across amplifiers that can operate normally at a resistance of 2 ohms than at 1 or 0.5 ohms.
Connecting a lower load resistance to the amplifier than its rated value may result in damage to the device.
You can calculate the resistance that will be after connecting the speakers in parallel using the formula:
R = (R1 R2) / (R1 + R2),
Where R is the load resistance for the parallel connection that we are looking for, and R1 and R2 are the resistances of the speakers that are connected in this way. For example, the resistance when connecting two eight-ohm speakers in parallel will be 4 ohms. When two speakers are connected in parallel, the output power of the amplifier for such a load will be twice as large.
Speaker combo connection

This connection diagram is used to obtain the required resistance for the amplifier. For example, in order to connect four speakers with a total impedance of 4 ohms. To calculate the load resistance using this connection method, use the formula:
R = (R12 R34) / (R12 + R34), where R12 is the total resistance of speakers 1 and 2, which are connected in series, and R34 is the same for speakers 3 and 4. If you have four 30-watt four-ohm speakers, then In such a connection scheme, the total power will be 120 W and the resistance will be the same 4 Ohms. And the power supplied from the amplifier will be equally divided among the four speakers.
Online calculator

http://www.rockfordfosgate.com/rftech#wiringwizard

It’s good if the installer has the opportunity to use a channel-by-channel amplification circuit. However, in most cases this is considered an unaffordable luxury, and during the installation of an audio system, in nine cases out of ten there is a need to load, for example, a two-channel device with four speakers or a four-channel device with eight.Actually, there is nothing terrible about this. It is only important to keep in mind a few basic ways to connect speakers. Not even several, but only two: serial and parallel. The third - series-parallel - is a derivative of the two listed. In other words, if you have more than one speaker per amplification channel and you know what loads the device can handle, then choosing one, the most acceptable circuit from three possible ones, is not so difficult.

Daisy chaining of speakers

It is clear that when the drivers are connected in a series chain, the load resistance increases. It is also clear that as the number of links increases, it grows. Typically, the need to increase resistance arises to reduce the output performance of acoustics. In particular, when installing rear speakers or a center channel speaker, which mainly play an auxiliary role, they do not require significant power from the amplifier. In principle, you can connect as many speakers as you like in series, but their total resistance should not exceed 16 Ohms: there are few amplifiers that can handle higher loads.

N Figure 1 shows how two dynamic heads are connected in a daisy chain. The positive output connector of the amplifier channel is connected to the positive terminal of speaker A, and the negative terminal of the same driver is connected to the positive terminal of speaker B. After which the negative terminal of speaker B is connected to the negative output of the same amplification channel. The second channel is built according to the same scheme.

These are two speakers. If you need to connect, say, four loudspeakers in series, then the method is similar. The “minus” speaker B, instead of connecting to the output of the amplifier, is connected to the “plus” C. Further from the negative terminal C, a wire is thrown to the “plus” D, and from the “minus” D a connection is made to the negative output connector of the amplifier.

Calculation of the equivalent load resistance of the amplification channel, which is loaded with a chain of series-connected speakers, is carried out by simple addition according to the following formula: Zt = Za + Zb, where Zt is the equivalent load resistance, and Za and Zb are the corresponding resistance of speakers A and B. For example, we have you have four 12-inch subwoofer heads with a resistance of 4 ohms and one single stereo amplifier 2 x 100 W, which cannot tolerate low-impedance (2 ohms or less) loads. In this case, connecting woofers in series is the only possible option. Each amplification channel serves a pair of heads with a total resistance of 8 ohms, which easily fits into the above-mentioned 16-ohm framework. Whereas parallel connection of speakers (more on that later) will lead to an unacceptable (less than 2 ohms) decrease in the load resistance of both channels and, as a result, failure of the amplifier.

Cog Yes, more than one speaker is connected in series to one amplification channel, this inevitably affects the output power. Let's return to the example with two 12-inch heads connected in series and one 200-watt stereo amplifier with a minimum load impedance of 4 ohms. To find out how many watts the amplifier can deliver to the speakers under such conditions, you need to solve another simple equation: Po = Pr x (Zr/Zt), where Po is the input power, Pr is the measured power of the amplifier, Zr is the load resistance at which the measurements of the real power of the amplifier, Zt is the total resistance of the speakers loaded on a given channel. In our case it turns out: Po = 100 x (4/8). That is 50 watts. We have two speakers, so the “fifty dollar” is divided into two. As a result, each head will receive 25 watts.

Parallel connection of speakers

Here everything is exactly the opposite: with a parallel connection, the load resistance drops in proportion to the number of speakers. The output power increases accordingly. The number of loudspeakers is limited by the ability of the amplifier to operate at low loads and the power limits of the speakers themselves, connected in parallel. In most cases, amplifiers can handle loads of 2 ohms, less often 1 ohm. There are devices that can handle 0.5 ohms, but this is truly a rarity. As for modern loudspeakers, the power parameters range from tens to hundreds of watts.

Figure 2 shows how to connect a pair of drivers in parallel. The wire from the positive output connector is connected to the positive terminals of speakers A and B (the easiest way is to first connect the amplifier output to the “plus” of speaker A, and then pull the wire from it to speaker B). Using the same circuit, the negative terminal of the amplifier is connected to the “minuses” of both speakers.

Calculating the equivalent load resistance of the amplification channel when connecting speakers in parallel is somewhat more complicated. The formula is: Zt = (Za x Zb) / (Za + Zb), where Zt is the equivalent load resistance, and Za and Zb are the speaker impedance.

Now let’s imagine that the low-frequency link in the system is again assigned to a 2-channel device (2 x 100 W per 4 ohm load), but operating stably at 2 ohms. Connecting two 4-ohm subwoofer heads in parallel will significantly increase the output power, since the load resistance of the amplification channel will be halved. Using our formula we get: Zt = (4 * 4) / (4 + 4). As a result, we have 2 Ohms, which, provided the amplifier has a good current reserve, will give a 4-fold increase in power per channel: Po = 100 x (4/2). Or 200 watts per channel instead of 50 obtained by connecting speakers in series.

Series-parallel connection of speakers

Typically, this circuit is used to increase the number of speakers on board a vehicle in order to achieve an increase in the total power of the audio system while maintaining adequate load resistance. That is, you can use as many speakers as you like on one amplification channel, if their total resistance is within the limits we have already indicated from 2 to 16 Ohms.

Connecting, for example, 4 speakers using this method is done as follows. The cable from the amplifier's positive output connector is connected to the positive terminals of speakers A and C. The negative terminals of A and C are then connected to the positive terminals of speakers B and D, respectively. Finally, a cable from the negative output of the amplifier is connected to the negative terminals of speakers B and D.

To calculate the total load resistance of the amplification channel, which operates with four heads connected in a combinatorial manner, the following formula is used: Zt = (Zab x Zcd) / (Zab x Zcd), where Zab is the total resistance of speakers A and B, and Zcd is the total resistance of speakers C and D (they are connected in series to each other, so the resistance is summed).

Let's take the same example with a 2-channel amplifier operating stably at 2 ohms. Only this time, two 4-ohm subwoofers connected in parallel no longer suit us, and we want to connect 4 LF heads (also 4-ohm) to one amplification channel. To do this, we need to know whether the device can withstand such a load. With a series connection, the total resistance will be 16 Ohms, which does not suit anyone. With parallel - 1 Ohm, which no longer fits into the parameters of the amplifier. What remains is the series-parallel circuit. Simple calculations show that in our case one amplification channel will be loaded with standard 4 ohms, while driving four subwoofers at once. Since 4 Ohms is a standard load for any car power amplifier, no losses or gains in power indicators will occur in this case. In our case, that's 100 watts per channel, equally divided among four 4-ohm speakers.

Let's summarize. The main thing when building such schemes is not to overdo it. First of all, with regard to the minimum load of the amplifier. Most modern devices can handle 2-ohm loads quite well. However, this does not mean at all that they will work at 1 ohm. In addition, at low loads the amplifier's ability to control the movement of the speaker cone is reduced, which most often results in "blurred" bass.

All three examples given above concerned exclusively the low-frequency section of the audio complex. On the other hand, theoretically, on one two-channel device you can build the entire speaker system in a car with mid-bass, midrange and tweeters. That is, with speakers playing in different areas of the frequency spectrum. Therefore, you will have to use passive crossovers. It is important to remember here that their elements - capacitors and inductors - must be matched with the equivalent load resistance of a given amplification channel. In addition, filters themselves introduce resistance. Moreover, the further the signal is from the passband of the filters, the greater the resistance.

Typically, the basic configuration of a speaker system without any quirks can satisfy all the needs of the average user. After all, the system is, as a rule, selected immediately for specific needs - for example, so that the power is enough to listen to music in a specific room. However, in some cases it may happen that the characteristics of the existing acoustics are no longer sufficient for the given operating conditions. Then the user begins to look for ways to upgrade the system at minimal cost.

Of course, the best option is progressive improvement - for example, replacing an old stereo pair with a modern multi-channel system. If financial capabilities do not allow you to buy a new expensive set of acoustic devices, it becomes interesting how to increase the number of speakers in the existing system. And here the question may arise: “Is it possible to connect another pair of speakers to the one already in use?” Answer: no, the speakers are not directly connected to each other. But with some reservations. In what situations can connecting speakers to speakers become possible?

Methods for assembling a speaker system

Strictly speaking, the speakers are connected to each other in any case - otherwise the integrity of the system would not be ensured, which is necessary to create uniformity and unity of the sound environment.

Connection details depend on the type of speaker system. It happens:

stereo – has two front speakers that receive a common signal from the two front channels;
multichannel – receiving a separate signal, one for each speaker.

In the first case, connecting the speakers to each other is either not required if different speakers are located in a common housing - for example, in the case of a tape recorder or radio, although this also occurs in conventional stereo pairs for a computer, or the speakers are connected by simply connecting the secondary device to the main one using a regular cable with 3.5 mm plug. Remember: the main column is the one on which the main outputs, controls and indicator lights are located. From the second there is only one wire coming off - the same one with which it is connected to the main one.

A multichannel system can involve both direct and indirect connection of speakers. In the second case, the speakers are combined only through the receiver or the sound card of the sound source itself - a device that divides the common signal into separate channels. This scheme is used, as a rule, when using active-type columns. If the speakers are passive and an external audio amplifier must be used, the circuit becomes more complicated. Typically, in this case, special speaker cables with terminals are used, which, unlike plugs, are not connected to connectors, but to two separate terminals.

Just like on a battery, the terminals have different poles - plus and minus, which should not be confused so as not to break electrical devices the first time they are plugged into the network. Any person should remember this from physics lessons. From there, you need to remember that electronic devices can be connected in two ways: serial or parallel. When connecting speakers to each other in this way, it is important to remember the need to match the electrical parameters - basically, the resistance indicator of all devices. The speakers must have the same impedance, and their sum should not exceed the impedance of the sound amplifier.

Series connection of speakers

As is known, when electrical devices are connected in series, their resistances are summed up. This property can be used to reduce output characteristics - for example, when connecting auxiliary speakers (rear or side), which do not require high power. As for the maximum number of speakers connected in series, this parameter should be calculated based on their own resistance. When summed up, the indicator should not exceed the maximum permissible resistance of the amplifier - most often it is 16 Ohms, a higher number is practically impossible to meet.

As the name of the method suggests, the devices must be connected one after another, forming a closed circuit. The wire from the positive terminal of the amplifier goes to the plus of the first speaker, the wire from the minus of the first column goes to the plus of the second, and the minus of the second is connected to the minus of the amplifier. Everything is extremely simple.

If more than two columns are connected, the circuit is exactly the same, only it has more steps. The main thing is to go from the plus of the amplifier to its minus, combining only opposite poles, with the exception of the beginning and end of the circuit.

In some cases, a serial connection is the only possible option. For example, you have two passive subwoofers with a resistance of 4 ohms and an amplifier with two channels of 100 W each. Such an amplifier, as a rule, cannot function if the signal supplied to it has a resistance of less than 2 ohms - this is exactly what it will be if the speakers are connected in parallel. However, when connected in series, the resistances of both subwoofers will add up, and as a result, a signal with a resistance of 8 ohms will be supplied to each channel of the audio amplifier. This is an almost ideal indicator - the limit of 16 ohms is still far away, and there is no fear of device failure due to lack of resistance.

It is worth considering that when connecting several speakers to one amplifier channel, the maximum power of the amplifier is divided equally among all devices, taking into account the resistance. So, an amplifier with a power of 100 W and a minimum resistance of 2 Ohms will deliver 100:2:2 = 25 W to each of the two speakers.

When the speakers are connected in parallel, all manipulations with physical parameters occur in a mirror order: the resistance drops and the power increases. But the columns in this case are not directly connected to each other, so this point will be discussed in another article.

Knowing the intricacies of all the ways to connect speakers to each other and other participants in the speaker system, it is easy to accurately calculate all the real parameters of the devices used.

In professional work with sound, it is very important to understand the basic principles of switching different types of equipment; this makes it easier and faster to achieve high-quality sound and extend the life of the equipment.

Considered in this light, three types can be distinguished: and acoustic systems. Each type has its own characteristics, which we will consider in this article.

So, we believe that you bought it. After unpacking the equipment, the first question that arises is the connection.

Active acoustics. The main difference between active and passive acoustics is the presence of an amplifier built into its housing. This means that the power of the sound signal supplied to the active speaker system (hereinafter referred to as the speaker system) is significantly less than to the passive one. Therefore, these speakers use their own cables and connectors designed for lower current and voltage.

Levels. Although line signal levels are standardized, inconsistencies between devices can still occur. Because in fact, in audio technology, not one standard is used, but several. The most popular line levels for audio equipment are +4 dB (1.23 V), -10 dB (0.25 V) and -10 dBV (0.32 V). As a result of a mismatch between the levels of the output device (for example, ) and the input device (for example, ) the signal may be distorted or receive a large level of noise. In this regard, on devices we can often see switches for the nominal output and input levels. If there is no such switch and there is no output level regulator, then you will have to use an additional matching device.

Balance and imbalance. For high-quality signal transmission, the cable suitable for the active speaker must be shielded. It is also important to understand that the connection can be balanced or unbalanced. An unbalanced connection (unbalanced) is a connection using a single-core shielded wire. A balanced connection (symmetrical) is a connection using two shielded wires. One of the wires transmits an unchanged signal (+), and the second transmits a signal in antiphase (-). Such signal transmission allows the use of devices that, based on signal subtraction, help to effectively combat interference and interference. In practice, an unbalanced connection is more often used as jumper wires between equipment, that is, when the source and receiver are located nearby. A balanced connection is recommended for use at a distance of more than 20 meters and allows high-quality signal transmission over 200 meters. The signal transmission methods in the connected devices must be consistent; the balanced input must be connected to the balanced output. Otherwise, adapters or devices for matching the signal transmission method are used.

Hi- z. The Hi-Z input is a high impedance input that provides an impedance-matched connection between the speaker system and the guitar's pickups. That is, it is an unbalanced input for acoustic guitar, lead and bass guitar. It is also called instrument input.

Use of optional patch adapters should be done with caution. It is necessary to take into account all the above-mentioned characteristics, they must match: the input and output must have the same nominal signal level (+4 dB, -10 dB, etc.), transmission method (balance/unbalance) and impedance (input and output impedance).

Connectors. Popular powered speaker connections include XLR, RCA, and TRS.

The most popular connector in speaker systems is XLR.

Known for its high reliability. Coming into sound from aviation, the XLR connector, or as it is also called “Canon”, has successfully taken root in most professional audio equipment. The three-pin type of connector is most familiar to us, although they come in four, five, and sometimes more-pin types. Almost always, the contacts on the connector are labeled: 1 - body and/or ground, 2 - plus signal (+), 3 - minus signal (-). It can be wired for both an unbalanced connection (pins 1 and 2 are used) and a balanced connection (pins 1, 2, 3). The connector uses a latch mechanism that locks the position.

TRS and TS connectors. The “Jack” connector comes in three-pin TRS and two-pin TS.

The abbreviation stands for contact designations: 1 - Sleeve (sleeve) ground and/or body, 2 - Tip (tip) signal plus (+), 3 - Ring (ring) signal minus (-). It is clear that the TS plug can only transmit an unbalanced signal. TRS can be wired for both balance and unbalance. The size of the connector can be quarter-inch (TRS1/4”) and 1/8-inch (TRS1/8”, 3.5 mm), also called a minijack.

A connector that is often used in both professional and household equipment is the RCA connector.

People call it "tulip". It is not the most correct connection of devices from an engineering point of view. This is because at the moment of connection the signal is connected as the first contact, and not the ground contact as it should be. However, thanks to its shape and low cost, it firmly occupies its position among the popular connectors. Transmits an unbalanced signal at line level.

Almost every modern professional active speaker has a pass-through output on an XLR connector in its housing.

This output can be called differently - Link Output, Mix Out, Thru Out, Line Out, but the essence is the same - to give the signal input to the speakers for further routing. Depending on the speaker model, the output signal may be absolutely identical to the input signal or undergo some changes. For example, an already limited signal or a signal after a high-pass filter can be sent to the output. If the speaker system has a built-in mixer for several channels, then the signal from only a specific input or the total signal from all inputs can be sent to the output. Such questions can be clarified by reviewing the instructions for the speaker. This connection concept allows you to create long lines of speaker systems without running a cable from the mixer to each speaker.

Also, the through output is used when connecting satellites. It is important to “place” all the acoustic systems used as a portal system on one stereo output of the mixer - Main Mix, in order to control the sound in the auditorium with one fader. Speakers performing monitor functions are connected to separate outputs of the mixer. Typically, in such a situation, the sound from the mixer from the Main Mix output is supplied to one/two subwoofers, and further from it/them, using the through output, the signal is supplied to the satellites.

It turns out that if you can connect one subwoofer with two satellites, and the sound is first supplied to it, then the subwoofer must contain two independent channels in order to send stereo to the satellites. Below in the picture we can see a diagram of a typical subwoofer panel with connectors.

Here the connections are made using balanced XLR connectors. The two channels are named A and B. Outputs: FullRange - full range of the signal, HighPass - signal after the high-pass filter. From the HighPass output, the signal from the subwoofer is sent to the satellites, from Full Range - to another subwoofer (if you have four subwoofers and two satellites).

Passive acoustics. When connecting passive speaker systems, you should start by checking that the power of the connected amplifier and the speakers match. This is the most important question. If the selection is incorrect, distortion (overload) of the amplifier's output signal appears, which can lead to damage to the acoustics. The output power of the amplifier should be equal to the power of the acoustics or 5 - 10 percent more. It is best to use an amplifier at 90% power (which corresponds to the maximum speaker power) than a lower power amplifier at 100% power, which does not reach the maximum speaker power ratings. If the amplifier power is insufficient, the acoustics will not “open up” completely. It is necessary to ensure that when selecting capacities, the power indicators of the same standards are compared.

Power. Manufacturers use power standards such as rated, peak, sine, DIN, RMS, AES, PMPO, Program power. And that's not all the existing power standards. Some powers are close in terms of performance, but still, do not forget that these are different powers! Such a variety of capacities can be justified by different standardization approaches in different countries. For Russia, the native standards are rated and sinusoidal power, DIN refers to the German Institute for Standardization, RMS, AES, PMPO are Western standards. The most objective indicators are the nominal (Nominal) and root mean square (RMS) power; the PMPO standard is considered the most “frivolous”, since it is difficult to truly objectively assess the power of speaker systems. There are formulas that allow you to at least roughly convert one power into the equivalent of another.

The easiest option for a buyer in selecting speakers and an amplifier is to choose devices from one company, since large companies usually produce specific series of amplifiers in conjunction with specific speakers, repeatedly checking the reliability of such sets and optimizing their operation. A hint can be provided by brochures produced by manufacturers, which describe the optimal options for combining series of amplifiers with speakers.

Resistance. It is important to remember to match the device resistances. So for an amplifier, the technical specifications usually indicate several powers for operating resistances (for example, 2000 W for 8 Ohms / 4000 W for 4 Ohms / 6000 W for 2 Ohms). The most popular speaker impedances are 8 and 4 ohms, and not every amplifier can work with 2 ohm impedances. These features echo the well-known concepts of serial and parallel connection of speakers. There are often situations when you need to load four speakers onto a stereo amplifier. If, for example, you connect four 4-ohm speakers to a two-channel amplifier in series, then their total resistance will be 16 ohms. We do not drop to dangerous resistance values, but we do lose power with this connection. With a parallel connection, the output power increases, however, in our case, the resistance drops to 2 Ohms. This means that the amplifier will run noticeably hotter due to the higher current. And in general, before using such a connection, you should make sure in the amplifier’s passport that it works with a 2-ohm load, otherwise there will be trouble. It is believed that at 2 ohms the amplifier's ability to control the movement of the speaker cone is reduced, which can result in a washed out bass sound.

Wire section. Everyone probably understands that although the cable resistance is low, it is there, which means it still causes a voltage drop. That is, the signal level drops, especially at high frequencies. The trick is that the resistance depends not only on the material and length of the wire, but also on its cross-sectional area. The larger the cross-section, the lower the resistance. The technical specifications for the cable must indicate the linear resistance. This means that, armed with a calculator, you can calculate, based on the length you need, what resistance the wires will have.

Phase. When connecting passive speakers, it is very important to ensure that the phases of the speakers match. This means that the cones of all speakers must move in the same direction at any given time. Usually, for convenient connection, the manufacturer marks the contacts on the speakers and the wires extending from them with marks (+) and (-). If the phasing is incorrect, the speaker cones will move in the opposite direction and thereby reduce to zero all repeating amplitudes in their signals. Since the bass component in a stereo signal is almost always the same (meaning a band in the range of approximately 30 - 130 Hz), this part of the signal will disappear in the “anti-phase” mode. In practice, you can see a picture when two speakers standing separately produce normal sound. When the low-frequency component is turned on at the same time, it disappears. This means that one of the speakers has the plus and minus contacts connected incorrectly.

Connectors. The most popular connectors for professional amplifiers are Speakon, XLR, TS, Euroblock, and screw terminals.

XLR, TRS/TS, Euroblock - used to connect the signal input to the amplifier.

Speakon, TS, screw terminals - for connecting speaker systems to an amplifier.

TS connector. The contacts are connected as follows: the signal contact (+) is connected to the Tip contact, and the signal contact (-) is connected to the Sleeve contact.

Speakon connectors come in three styles: 8-pin, 4-pin, and 2-pin. The most popular are 4-pin - they are used to connect two-way speakers. To connect three-way ones, 8-pin ones are used. Thanks to its design, it is a very reliable connector. After connecting to the socket, the plug must be turned clockwise to secure the contacts.

Screw clamps allow you to fix wires with special metal clamps and simply stripped bare wire ends.

Routing. Most modern stereo amplifiers have routing modes available. Stereo, Parallel, Bridge. Typically the two channels are labeled "A" and "B". Mode Stereo provides operation of two independent channels, mode Parallel provides parallel supply of a signal from input A to output A and B, while input B is not active, but each output has its own volume control, and the Bridge mode will help provide maximum power to one speaker, while control A is active .

Connection diagram (Stereo mode):

Connection diagram (Parallel mode):

Connection diagram (Bridge mode):

In the above diagrams, the speakers are connected in bridge mode using screw terminals. However, this is not the only connector on which bridge mode can be implemented. Let's take a closer look at this connection on the Speakon connector. Connector pins:

To connect the bridge mode, the wires are connected to the output contacts of channel A (pins 1+ and 2+):

Connecting speakers to an amplifier using Speakon connectors for parallel and stereo modes is the same, the only difference is in the routing itself inside the amplifier.

Stereo mode:

Parallel mode:

It can be seen from the diagrams that the stereo connection can be made either on two Speakon connectors or on one. With a double connection, contacts 1+ and 1- are used on each connector; when two speakers are connected to one connector in one plug, all four contacts 1+, 1-, 2+, 2- are used. Changing modes in the amplifier can be implemented in the form of a physical switch or in the control menu of the DSP processor.

Division into stripes. The next question is inextricably linked with the previous one. Since a professional amplifier can work equally well with both wide-range speakers and subwoofers, it is very convenient when the amplifier is equipped with a built-in crossover. This eliminates the need for additional hardware and additional switching. Since when using satellites with subwoofers it is recommended to cut off the low-frequency component, an amplifier with a built-in crossover must implement three functions - low-pass filter, high-pass filter, full range.

Let's consider options for connecting speakers to one two-channel amplifier with a crossover. Let's start with something simple.

Normal stereo mode with two full-range speakers:

Mono mode with one subwoofer and one satellite:

This mode is preferable to use when a stereo signal is not required, but increased demands are placed on the bass response.

Biamping and biwiring(Bi-Amping and Bi-Wiring). To consider the next connection you need to understand what biamping is. Biamping is a connection scheme in which each speaker of a two-way speaker system requires a separate amplifier channel. That is, such a speaker simply does not have a built-in crossover and each of the two channels supplied to the speaker must be respectively tuned to the low-frequency or mid/high-frequency band. Biwiring is a connection scheme in which wires from one amplifier channel are connected separately to the woofer and mid/high frequency speakers. Since they are still connected to one channel of the amplifier, it turns out that it must be broadband, which means that the speaker system must have a low-pass and high-pass filter installed for each speaker. That is, the same crossover, only on some kind of separate structure with filters. The benefits of this connection method are questionable, unlike biamping. Biamping can be useful in cases where, for some reason, it is impossible to place a crossover in the speakers.

Connecting a two-way speaker using a biamping scheme:

All principles of matching an amplifier and speakers are also relevant for multi-channel amplifiers. The difference is only in the number of channels and speaker systems; routing of such amplifiers also becomes more complicated. Any multi-channel amplifier can theoretically be replaced by a set of two and single channel amplifiers.

In addition to the connections of active and passive speaker systems that we have considered, we can also touch upon a separate area - the connection of broadcast speaker systems.

Broadcast acoustics. This equipment is fundamentally different from passive and even more so from active acoustics. The peculiarity of broadcast systems is that thanks to the use of step-down and step-up transformers in the designs of amplifiers and speakers, high-quality sound transmission over long distances is achieved. Therefore, this sound system is in demand in enterprises, offices, supermarkets, etc. Naturally, without much experience, it is very difficult to design and configure a broadcast system yourself; it is better to entrust this task to professionals.

Let's consider the basic principles of connecting broadcast speaker systems:

There are broadcast lines with signal voltage levels of 240 V, 100 V, 70 V, 30 V and others. The AC terminals must correspond to the line voltage, that is, have the corresponding input voltage;
when connecting speaker systems to an amplifier, remember that their total power should not exceed the power of the amplifier;
With 100 V and 70 V amplifier modes available, speakers can be switched from a 100 V line to a 70 V line. In this case, the power of these speakers will drop by half, at the same time their number can be doubled.
Some speakers have leads not only for high-impedance loads, but also for low-impedance loads. Usually the purpose of the contacts is written on the case; it is important not to confuse them when connecting.
selection of AC transformer terminals - the lower the AC resistance you choose, the more power it will produce.