Every car enthusiast who wants to improve the acoustics in his vehicle probably knows what a subwoofer and an amplifier are. However, not everyone knows for what purpose these devices are intended and how to choose them correctly. From this material you can learn about what a car acoustic amplifier is, what functions it performs and what to look for when choosing a device.
Technical features
So, why and why do you need a car tube or other speaker music amplifier with a built-in or external power supply? First of all, this device is designed to increase the power level of the impulse signal, as well as improve the sound of acoustics. Amplifier is needed for those who cannot imagine their ride without powerful and high-quality music.
A car audio amplifier is an electronic device that, although considered part of an acoustic system, is a separate component. Most modern car radios today are equipped with their own amplifiers (built-in), however, in practice, the power supply of such devices is usually low and does not meet the needs of the motorist.
As you know, a tube or digital amplifier of good power with a power supply can be installed in any part of the vehicle, but usually drivers install it in the trunk or under the seat. In any case, the main parameters of the device are the output power, as well as the frequency range. A lamp or digital device to improve the acoustics of speakers must be selected taking into account a certain power reserve. Actually, it is the power that is the main indicator of the device, the power is selected taking into account the front and rear speakers. For front and rear speakers, the power level should be 75-100 watts, the power for the subwoofer should be from 150 to 300 watts.
By their design, regardless of class, devices are digital and analog. Digital devices are designed for digital signal processing, analog - electrical. As practice shows, digital devices sound amplification makes it possible to select individually adjustable parameters. Such processing makes it possible to memorize certain frequency characteristics for a separate speaker.
The design of digital devices may include:
- Cascade filter element. The filter is needed to amplify or attenuate the pulse amplitude in a particular frequency range.
- Delay module. This element is needed to delay the pulse for the rear frequency by a few milliseconds. In addition, the device allows you to enhance the effect of presence.
- Distortion limiter element. This component is needed to support a low total harmonic distortion (video by Loud Sound).
The frequency properties of the device make it possible to adapt to certain features of the vehicle interior. Accordingly, this characteristic makes it possible to attenuate the frequency ranges that interact with the interior components. And if certain frequencies are weakened by the sound-absorbing components of the car interior, then the frequency characteristics will allow them to be amplified.
Criterias of choice
Why do you need a tube or another class of amp in a car - we figured it out. Now we will consider the aspects that must be considered when choosing a device. Let's start with the classes.
Amplification class
- Class A. This type of sound amplification is the least effective and one of the most correct. A device of this class allows you to play audio tracks with the lowest distortion, while such devices generate and consume a lot of heat. Although the devices have certain advantages, they are practically not installed in the car due to too high noise in the cabin.
- Class B. As for class B devices, they are devices that are 100% opposite to the previous ones. Such devices are often used by motorists as a result of their high sound reproduction efficiency as well as thermal stability.
- Devices of type AB represent something in between devices of type A and B. Such devices are the most common among our compatriots. Why do motorists choose them? Because of the good efficiency, as well as a fairly good level of distortion.
- Type D audio devices are considered digital and operate in a different way from the ones described above. If previously such devices were used to amplify low frequencies of audio, today manufacturers are increasingly using wideband amplifiers. According to experts, over time, type D devices will be able to surpass AB devices in quality, but today the latter are still more practical.
- Others. There are also other types of devices - C, T and others. But in practice they are used in vehicleoh, quite rare (the author of the video is avtozvuk).
Number of channels
All audio devices with an integrated processor and power supply, whether tube or other, use a different number of power channels. Most the best option is the use of a fixture that provides an amplification channel for each individual speaker. In the event that you are using an acoustic system with a passive device, several separate speakers can be connected to one channel. It should be remembered that any audio track that is played through a tube or other amp with a processor and power supply has at least two channels.
So, what types of connection can be used in a tube or other amplifier with a built-in processor and power supply:
- Front speakers + rear. This option is one of the most popular among our compatriots. To implement such a scheme, four channels are required, but it will not be relevant if you want to achieve the highest quality sound of audio tracks. This is because the rear acoustics pulls the sound back, and brings certain distortions to the fore. This option will be more relevant for those motorists who like listening to audio with the “surround sound” effect. It should be noted that low frequencies will not be reproduced without a subwoofer.
- Front speakers with subwoofer. If you want to achieve good quality when listening to audio tracks on your car using a tube or other amplifier, then this option will be the most optimal. For normal work circuits required three or four free channels. Two channels can be used with bridging, where bridging is a circuit that combines two speakers into one channel to increase power.
- Front speakers with rear and subwoofer. This option is almost completely identical to the first one considered, only with the addition of a sub. To implement it, five or six channels are required.
- The so-called auto-cinema Is one of the least common options. This arrangement includes front and rear speakers, a sub, and center. To implement it, six or seven channels are needed (the author of the video is Autosound School of Sergey Tumanov).
In practice, tube or other amplifiers with a built-in processor and a two-channel power supply are most often used. If your financial capabilities are limited, then six- or four-channel devices can be used to implement the scheme. If everything is clear with the number of channels of a lamp or other device, then we proceed to the selection of the basic properties.
Amplifier power
In tube and other amps, there are two power levels - nominal and maximum. The nominal value is usually measured at 1 percent distortion, as for the maximum, it is measured without distortion. The indicator is in any case determined in the presence of a load resistance. So, if your speakers or sub are characterized by different resistance, then this should be taken into account.
It should also be noted that the level of the output parameter will directly affect the quality of the audio signal negatively. If the vehicle is equipped with a good speaker system, then a more powerful amplifier will in any case work worse than its less powerful counterpart if the above parameters are equal.
How to choose an amplifier for a car and choose all the parameters correctly:
- When buying a tube or other amplifier with an integrated processor and power supply, it is advisable to rely on devices from popular brands. Devices from more popular companies are usually characterized by high qualityif the brand has a reputation, of course.
- When buying a lamp or other device with a power supply and an integrated processor, you need to choose the right power. Experts recommend using audio channels with a power level of 70 to 120% of the system power level. If the amplifier is weaker, then it will not be able to cope with the control of the speaker, and if you choose a more powerful device, then when playing audio you will notice quality loss.
- In the event that you decide to pick up a device with four channels that will work with subwoofers and front speakers, then it is better to opt for options with several power supplies.
- Remember that the declared properties and characteristics of the device do not always correspond to the actual ones.
TOP best amplifiers
Pioneer GM A3602
A budget option that occupies an honorable place in our rating. The rated power level of this two-channel device is 2x60 watts. Of course, the device can also function in a bridged connection. The A3602 model, which got into the rating, cannot boast of extensive functionality, but it has all the necessary settings.
If necessary, the motorist can always configure the sensitivity and adjust the low-frequency filter element. This rating device has a high level input for or audio systems that do not have a line output.
Alpine PMX F640
The Alpine PMX F640 included in our rating has the same dimensions as the amplifier described above, but belongs to the A / B class and has four channels. Characteristic feature This device is considered compact, due to which hidden installation of the device is possible. The F640 amplifier in our rating has a power of 4-50 watts, if necessary, a two-channel can be made from a four-channel device. This unit is equipped with a set of adjustable low and high pass filters for two speaker groups separately.
DLS RM30
The next device that got into our rating is the DLS RM 30. The three-channel device is designed to work with front speakers and a mono sub. This option will be most optimal if, instead of rear acoustics a sub is used in the vehicle. In addition, the rated DLS has a more advanced configuration in terms of subwoofer channel settings. The developers of the amplifier made sure that the installation of the device with their own hands did not cause problems for the buyer. Therefore, the terminals for connection to the cables are installed downward.
Alpine MRX-M240
The Alpine MRX-M240 is another amplifier to make the list. The device is completely subwoofer, it is a unit with installed cooling fins. If necessary and properly arranged, the acoustics can deliver power at a level of 1500 watts. Such a device, which made it into our rating, usually does not connect to factory audio systems that do not have an appropriate output for a sub. These devices are equipped with a high-voltage acoustic input, if necessary, a car enthusiast can connect a remote control that will allow you to adjust the bass level.
Video "What should be considered when choosing an amplifier?"
Good afternoon, lovers of high quality car audio !!! In this article I will talk about the simple truths of adding and choosing an amplifier in a car, however, and for the experienced, this article will reveal a lot of new knowledge. I really hope that this article will help at least some people looking for high quality sound in a car.
Why add an amplifier to your car?
If you want your music to be loud, then you will need an amplifier in your car, which will certainly be part of your system. Whether yours is good or bad, a car power amplifier will breathe life into your music. Here are some of the main benefits of adding an amplifier to your car:
- More... Adding an amplifier will give you a clean power source that drives your speakers without straining. Unlike an amplifier built into a stereo radio, an external power amplifier is not limited in the available circuitry space. This means that your music in the car will sound cleaner at all volume levels.
- Power for the speakers of a standard radio may not always be enough for car speakers... If you add high-quality acoustics to your car's system, they may require more power for peak performance than your existing radio.
- Connecting a subwoofer to a car... Subwoofers require significantly more power. A separate amplifier is a must for the sub. 
Standard stereos, especially standard factory ones in cars, as a rule "give out" no more than 10 W RMS of maximum output power per channel, despite the fact that they are advertised as 4x50 or more :). They, as a rule, do not have enough power to overcome even road noise; there can be no question of high quality sound amplification. A great way to upgrade your speaker system without changing the factory appearance your car, this is a factory rebuild of your stereo system. This system includes an amplifier and other sound processing devices specially designed for your specific vehicle, which will greatly improve the sound and make you hear high quality sound in your car.
A more economical way to upgrade your speaker system without changing your factory receiver and speakers is to put a compact 4-channel amplifier in your car to boost the power for your front and rear speakers. Clarion XC1410, with a 4-channel amplifier as an example of an amplifier that is small enough but can be mounted behind a panel and can be powerful enough to dramatically improve sound quality and clarity.
Your speaker manuals say RMS (or "continuous") power ratings, usually in the form of a range of "5-60 watts RMS power". The higher the number represents 
the approximate power at which the speaker will play to its fullest, then it is the best according to the manufacturer. In fact, most car speakers are very poor in terms of structure / components and sound. But they really won't sound good if they can't get at least three-quarters (75%) of that power.
If your front and rear speakers are slightly different in your car, then don't worry if you can't find an amplifier that's powerful enough to match your low power speakers. You can always install an amplifier in the car, moreover, it will never reach its full powerand the speakers will be safe.
Many people use music with front speakers and don't use rear speakers. A 2-channel car amplifier will be a practical solution for them when amplification is needed for only one pair of speakers. But if you are using the rear speakers as volume filling in your car and you want to keep the front speakers as the main ones, then you need a 4-channel amplifier - one channel for each speaker.
There are some other amplifier configurations for auto
3-channel amplifier can take care of one pair of speakers plus a sub.
4 channel amplifier It can also be used for a pair of speakers and a subwoofer, and you need to connect two channels with a bridge to start the sub "at full", and the other two to control 2 speakers in stereo. This gives you the option for future expansion of your system in the car, allowing you to later change the amplifier and connect four speakers and add a separate amplifier for the subwoofer. Finally, there are amplifiers 5-channel for carin one convenient and compact package.
I am planning to put new speakers together with my new amplifier in my car
When building a system from scratch, one of the first questions that you have to ask yourself, "How loud do I want to listen?" A car audio system does not need to be powered by a powerful amplifier to sound loud, but the available energy must have a "headroom" with the potential for emotionally exploding music or movies.
If you are driving a compact coupe or hatchback, sports car, or pickup, then 50 watts RMS per channel, or less, this amplifier will overcome road noise well and add clarity to your music. Look for speakers with a powerful RMS of at least 35W to match perfectly with your amplifier. 
For larger vehicles and those who just want more volume, you need to choose an in-car amplifier with at least 75W RMS per channel. Although a difference of 5 or 10 watts won't make any difference anyway and probably can't even be heard.
For those of you who want even more sound and stunning bass for your in-car system, you will need to opt for an amplifier with 100W RMS or more per channel.
I'll just add a subwoofer
Much harder to amplify than the rest of the sound - which is why there are so many large and muscular subwoofer amplifiers in audio salons, made solely for low frequency reproduction. Mono or 1-channel amplifiers are designed to work with a wide impedance range, they have tone controls and specially designed filters to help 
reproduce thundering in a car. Although many two-channel and 4-channel amplifiers can amplify enough sound to drive a subwoofer, they often cannot cope with low impedance later, and overheat or “go into protection mode”.
You want the bass to be musical, unmixed and well balanced with the rest of your system, then you need an amplifier for your car - 50 to 200 watts RMS.
You must know the impedance of your amplifier and. It will be a waste of money if you buy a pair of subwoofers and an amplifier, for example, but then you find out that the amplifier cannot work, because by connecting them with each other, the resistance will be too low for the amplifier, it will certainly work, but it will be permanent overheat.
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Good luck with all kinds of auto sound combinations!
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Bass Amplifiers are an integral part of your home sound reproduction system. They are used as power amplifiers for low-power playback devices and for achieving signal parameters capable of "shaking" the speaker system. There are also playback devices with built-in power amplifiers, but often their technical specifications and functionality is poor. Therefore, many high-quality sound lovers often resort to buying an external amplifier that best suits their needs. In this article we will try to help you understand which amplifier to choose for your home.
Amplifier types
According to their functions, amplifiers are divided into three groups:
- Pre-amplifiers. They are used to prepare a low-power input signal for further amplification. They are usually placed close to the signal source to avoid pickup and interference from other electrical and electronic devices... As a rule, they consist of an input switching unit, a volume and tone control unit and the amplifier itself, which amplifies the signal to a level of 1-2 V. Preamplifiers require the use of a power amplifier;
- End amplifiers (power amplifiers). Their purpose is to amplify the signal to the level and power required for the normal operation of the acoustics. They, as a rule, lack the ability to adjust any signal parameters;
- Complete amplifiers. They simultaneously perform the functions of a pre-amplifier and a final amplifier, therefore, they provide more operational convenience. In addition, their cost is often less than the total cost of separate preamplifiers and final amplifiers.
- Tube amplifiers. Their advantages are:
- high sound quality with a relatively simple circuit;
- less harsh and warmer sound;
- lower noise level;
- softer signal limiting during overload;
- resistance to short circuits in the load.
- Transistor amplifiers:
- They are based on the use of field-effect and bipolar transistors as amplifying elements. To achieve approximately the same parameters with tube amplifiers, transistor amplifiers require more complex circuitry. Also, unlike tube amplifiers, special requirements are imposed on them to protect the output stages and power supplies from overloads and short circuits. Today, instead of transistor amplifiers based on discrete elements, devices based on integrated circuits are often used;
- Amplifiers on integrated circuits. Typically, an integrated circuit chip contains all the main stages of a full amplifier. The advantages of such amplifiers include their compactness, the minimum number of external elements and high maintainability;
- Hybrid amplifiers. They use simultaneously both electronic tubes and semiconductor devices and integrated circuits with all their advantages and disadvantages.
Basic parameters of amplifiers
The sound quality of the amplifier in most cases is determined by the parameters of the final amplifier, both separate and included in the complete amplifier. Therefore, further discussion on the choice of an amplifier for the home will relate specifically to the final amplifiers.
What parameters should you pay attention to when choosing a home amplifier? These parameters include:
- The number of amplifying channels;
- Power developed in load;
- Distortion factor;
- Working frequency range;
- Slew rate of output signal;
- Signal to noise ratio.
Amplifier channels
The number of channels is selected depending on the configuration of the speaker system according to the principle "each speaker should work only from its own channel, and no channel should work for more than one speaker." Only this principle will ensure the highest quality sound. It should be said separately about the choice of amplifiers for music reproduction and AV-receivers for home theater. The first of these should have two channels for playing stereo formats, in which most of the music is recorded. Home theaters can be equipped with acoustics with a configuration from the most affordable 5.1 to top-end 9.2. This is the criterion for choosing the number of channels in an AV receiver.
Power developed in load
Professionals in the field of audio engineering give this advice: if there is a need to purchase an amplifier and a speaker system, then you should first select and buy acoustics, and then the amplifier. Firstly, it is much easier to choose an amplifier for acoustics than vice versa, and, secondly, the acquired acoustics provides some guidelines for choosing an amplifier, at least in terms of its power. These guidelines are as follows:
- Most amplifiers will perform at their highest performance at about 70% of their power. For acoustics, the same parameter is approximately 90%. Therefore, the most optimal is the ratio of acoustics power to amplifier power, equal to approximately 1: 1.6. In other words, the amplifier must provide 60% power. high power acoustics;
- Many manufacturers tend to indicate the maximum power of the amplifier. You need to focus on its rated power, since it is this that determines the long-term reproduction of sound with a given level of distortion;
- The power of the amplifier is related to the sensitivity of the acoustics. The latter is measured in decibels. There is a simple relationship: reducing the sensitivity of the system acoustics by 3 dB requires a twofold increase in the amplifier power to obtain the same volume.
Distortion factor
It consists of two indicators - the intermodulation distortion factor and the harmonic distortion factor. Both of them are set in percentage and determine the level of sound distortion at the amplifier output. As a rule, Hi-Fi class amplifiers comply with the DIN 45500 standard, which sets the following values \u200b\u200bfor these parameters:
- Intermodulation distortion coefficient - no more than 3% in the frequency band 250 - 8000 Hz;
- Harmonic distortion is less than 1% in the frequency range 40 - 12500 Hz.
Working frequency range
The hearing organs of most people are able to perceive sounds with frequencies from 20 Hz to 20 kHz. An ideal amplifier should have a straight amplitude-frequency characteristic (AFC) in this range. Real amplifiers usually rarely have a direct frequency response, as a rule, it has some unevenness in the operating frequency range, especially in its high-frequency region. Therefore, it is advisable to choose an amplifier with the widest possible frequency range, the optimal upper limit of which should exceed 20 kHz several times.
Slew rate of output signal
This parameter determines the ability of the amplifier without distortion, more precisely, with a given value of the distortion factor, to reproduce sharp bursts sound signal - the so-called signal edges, which often occur, for example, when hitting cymbals. In professional audio engineering, the term "response time" to a step change in the input signal is often used. This parameter is inextricably linked with the upper limit of the reproduced frequencies - the higher it is, the higher the value this parameter... For a high quality amplifier, this parameter should not be less than 5V / μs.
Minimum permissible load
The power developed by the amplifier and its reliability and reliability depend on the resistance of the load, that is, the speaker system. Obviously, a 4-ohm speaker will load the amplifier channel much more than an 8-ohm speaker. Conclusion - for acoustics with low impedance, a more powerful amplifier is needed. But do not forget that connecting a 4-ohm acoustics to an amplifier designed to work with an 8-ohm load, it can overload and even fail. Therefore, it is the minimum permissible load value that should be taken into account. On the other hand, if the amplifier is designed to work with a 4-ohm load, then it may not develop full power at loads with high resistance, which is not so important with a large margin.
Signal to noise ratio
This parameter determines the ratio of the power of the useful and noise signals. Measured in decibels at the maximum position of the volume control with the input signal turned off. The higher the value of this parameter, the better the quality of the reproduced sound. It is advisable to choose an amplifier with a value of this parameter of at least 90-100 dB.
- The choice of an amplifier model does not always come down to its cost and manufacturer's prestige. However, buying a too cheap model is also unreasonable - you should not hope for a miracle, although they do happen.
- Buy an amplifier in stores that do not have the opportunity to check it in real conditions, it is possible only after having decided in advance on the choice of its model.
- It is necessary to choose an amplifier with a power reserve so as not to operate it at powers close to the maximum, because this sharply reduces the reliability of the device. For example, an amplifier with maximum power 100 watts will provide long-lasting and reliable performance only at about half the power.
- It is also necessary to focus on the area of \u200b\u200bspace in which the sound reproducing equipment will be used. The approximate power of each channel is 3 - 5 W / m2. If the area does not exceed 15 sq. m., then you need to be guided by the first figure, and with areas of more than 20 sq. m. - the second.
- It is advisable to choose an amplifier for which the acoustics are connected not using spring latches, but using terminals with threaded clamps. This is, firstly, a more reliable fastening of cables, and secondly, it is some evidence of the constructive quality and belonging of the device to the Hi-Fi class.
- You don't have to buy the most latest model... It happens that an amplifier that has been lying on a shelf or warehouse for a long time becomes significantly cheaper without affecting its quality.
Installing a car audio amplifier will not only increase the overall power of your music system, but will also significantly transform the sound quality and detail of music fragments. Among other things, you can use music speakers separated on the sides and an additional speaker cable connected to each other.
Amplifier benefits for cars
Excellent sound quality. Using a stereo amplifier will allow you to optimize your sound automotive system... Connecting through improves the perception of sound across the entire audio frequency range.
You need to consider the fact that onboard voltage in a car is not always enough to provide the power output of an audio amplifier. In particular, this is manifested with subwoofers, the output amplitude voltage cannot adequately swing powerful low-frequency speakers.
This problem can be solved by using an amplifier with high-capacity electrolytic capacitors, which allow accumulating the necessary discharge and making the bass extremely juicy and of high quality. You can find out how to connect a capacitor to a subwoofer. Most car owners install additional subwoofers on their cars, which improves the quality of the standard audio system.
To connect a subwoofer, you need to use an additional amplifier, which will allow you to swing even a powerful sub. Most of the car audio amplifiers used today have additional outputs for the subwoofer and speakers in the car. That is why, by installing high-quality amplifiers in the car, you completely solve the problem with the organization of high-quality sound.
The car owner can improve the sound quality of the OEM audio system without replacing the head player and speakers. It is only necessary to install an additional four-channel amplifier, which is compact in size and boasts high power. In most cases, the installation and connection of a four-channel amplifier is not difficult and can be done independently.
At the same time, it should be noted that most of the standard audio systems in the car have a mediocre speaker quality, so if you want to get really high-quality sound in your car, we recommend installing not only an additional amplifier, but also replacing the existing standard speakers.
In this case, the car owner gets ample opportunities for the location of the speakers and the choice of their components. Many are limited to installing spaced apart front speakers with tweeters and tweeters.
In this case, when using such an acoustic scheme, a four-channel amplifier will be simply necessary for you. On sale, car owners can find compact modelsthat can be easily installed in the glove compartment or inside the center console.
Car speaker configurations
When choosing an amplifier, you should keep in mind that three-channel amplifiers are designed to work with one pair of speakers and an additional subwoofer. A four-channel amplifier can drive a subwoofer and two pairs of speakers at the same time. On rare occasions, five-channel stereos are used with lots of speakers in the car.
We build an audio system in a car from scratch
When planning and installing an audio system in a car, you first need to decide on its components and power indicators. You should remember that using a powerful amplifier will allow you to improve the sound quality at low volumes. Therefore, it is recommended to take the amplifier into a car with a small power reserve. In addition, you must consider the volume of the vehicle's interior.
Therefore, for a compact urban kid, you can choose the power of the audio system slightly lower than for a full-size station wagon or SUV. In this case, the best choice would be to use a 75W amplifier per channel for an SUV and 50W for a small car. For lovers of bass and loud music, we can recommend choosing systems with a power of 100-200 W per channel.
Installing the subwoofer
It is the low frequencies, or as they are also called bass, that play almost the main role in the perception of the sound picture. That is why many car owners decide to install special speakers in their car, which are responsible for reproducing low frequencies.
If you are comfortable with the power and quality of the existing stereo speakers in your car and just want to add a subwoofer, you can use a single-channel amplifier that will exclusively work with the subwoofer. In this case, you need to select the amplifier power in the range from 50 to 200 watts per channel.
Also, when purchasing an amplifier and subwoofer, impedance must be considered. This figure must be consistent, otherwise you will lose significant output power. Any difficulty in conducting installation works no.
If you have any difficulties, you can use the Internet and the YouTube service, where you can find numerous videos on the installation of an audio system in a car.
In our opinion, this article is useful in that it touches on fundamental, one might say - eternal, issues of High Fidelity. The author, who understands the essence of the problem well, is not by hearsay familiar with the hardships that haunt the unprepared for self-choice buyers. For novice audiophiles, the material is valuable because the author's experience is presented in the form of a short list practical advice: "The devil is not so terrible as he is painted" ...
The forums of specialized Internet portals are filled with questions: how does amplifier X work with acoustics Y? The answers either reflect the specific tastes of the owner of a particular system, or generate a host of counter questions. In addition, a verbal description of the nature of the sound rarely contains a sufficient amount of information necessary for an individual choice of audio equipment. Where to start for the unfortunate neophyte, dejected by the abundance of equipment of the most varied class and price? With the acquisition of acoustics (experienced men advise not to save on it)? Or from an amplifier? Which one of possible options behavior to choose? Let's take the liberty of giving a potential buyer fairly simple recommendations that were born from the experience gained by the author in practice ...
Boring theory
To be serious, the issues related to an objective assessment of the intricacies of the interaction between the amplifier and the speaker system cannot be solved overnight (and, by the way, have not been completely solved by anyone in the world yet). Technical experts Stereo & Video has been comprehensively studying the problem for several years, developing original methods for obtaining an exhaustive assessment of this phenomenon (however, it has not come to publication yet). "Pair" interaction is both a problem and a happiness of the hi-fi industry. The lack of common solutions gives rise to an army of audiophiles who are ready to listen to and change the speaker / amplifier combinations indefinitely. In turn, this contributes to an increase in the income of production, each year throwing new model lines equipment. At the same time, a serious developer, releasing a specific amplifier (or acoustics), tries with a margin to endow the model with the properties of universal communication. Otherwise the Y speaker will never "marry" the X amplifier! The consumer's doubts can be understood, but in most cases, when it comes to budget Hi-Fi equipment, these concerns are simply unnecessary. It would seem that compatibility problems should be solved at a high level when designing ready-made systems (music centers, AV-complexes, etc.). And what do we see besides general words? Complete absence the possibility of modernization by replacing system components plus the manufacturer's clear desire to save on everything and everyone. Maybe the problem is solved in expensive equipment, inaccessible to a wide range of consumers? Indeed, when the budget is unlimited, the developer is rescued by a frontal approach: a monster amplifier with almost unlimited possibilities and submissive acoustics, which have no right to even be a little capricious (everything is smooth: both the frequency response, and the impedance, and the phase response) ... There is another way - creation of the so-called active acoustics, which has built-in multiband amplifiers and precision crossovers active type... Such systems have taken root in the professional environment; for home use, the offer of such equipment is extremely limited - it is troublesome and unprofitable for the mass hi-fi industry to make high-quality active acoustics. Fabulous High End costs a lot of money, but the consumer is again unhappy. It turns out that among the wealthy audiophiles, the number of unfortunate seekers of absolute harmony is growing exponentially. Alas, these are the paradoxes of consumption.
First - the amplifier
You can choose an inexpensive Hi-Fi amplifier (or AV receiver) by presenting four elementary requirements to it.
First: minimal permissible load should not be 8 (or 6), but 4 ohms. In this case, you will not be bound by any restrictions on the permissible load resistances from the side acoustic systems (AC). The speaker impedance (impedance) is usually indicated as a number from the row 2, 4, 6, 8, 16 Ohm. Most often, 4-, 6- or 8-ohm acoustics are found, although, strictly speaking, the impedance varies with frequency and can drop to 1-2 ohms (usually in the low-frequency region) or, conversely, take off to 30-50 ohms. It seems that the safety of the amplifier should come first. If its output stage fails for any reason and it becomes necessary to contact the service center, then warranty repair you may be refused on the basis of violation of the rules of operation. Therefore, it is better if your chosen one (stereo amplifier or AV receiver) is "officially" ready to work with a minimum load of 4 ohms, which indirectly indicates the quality of the power supply.
Second, the maximum power output must match ... the size of the room. For example, a value of 30-50 watts per channel is perfect for a 12-15 square meter room. m. For a dwelling of 20-30 "squares" such power under certain conditions may seem modest (extremely insensitive acoustics, passion for the concert sound level). In order not to twist the volume control to the limit and not experience inferiority complexes on this, the power reserve will not hurt. There is also a more serious reason: an amplifier operating at the limit of its capabilities is a potential source of nonlinear distortions associated with the appearance of higher harmonics, which, in turn, increase the risk of destroying tweeters. This means that it is useful to take a more powerful device, for example, 100-120 W per channel. But what about the speakers? Do not be intimidated by this figure, even if the acoustics are designed for lower power, just try, as they say, to control the process.
Third, a decent amplifier should have output screw terminals for all channels, not spring-type holes for cables. This simple design detail indicates the level of claims of the developer himself. It is known that when a mass product is released, each item is counted. For example, the front panel is made of metal, not plastic, a heavy transformer and powerful radiators for cooling the output transistors (not microcircuits!) Are in a sense a sign of a Hi-Fi class.
Fourth: one should not always strive unconditionally to acquire the most new model... Often, a stereo amplifier that has been in stock for a year or two is seriously cheaper without any damage to quality. After the first power-up, it is enough to leave the device under current for a couple of hours without giving a signal to reduce the leakage of electrolytic capacitors to normal. An outdated AV receiver is another matter; here you need to know exactly which multichannel audio decoders you need and which you don't.
You ask, what about the numerous technical parameters printed in small print on the last page of the operating instructions? The vast majority of modern amplifiers budget class has very similar characteristics, which greatly simplifies the problem of choice. Of course, if the amplifier is supposed to spend completely "different" money, then it will take longer to think. And one last thing: some seemingly insignificant details can greatly influence your choice (the author, for example, hates golden cases). Consider whether you need a remote control, a turntable input or a preamp output?
Now - acoustics
If the list of models of amplifiers and AV-receivers on the market can easily fit into 3-4 pages of magazine text, then the situation with acoustics is much more complicated. In the price range from $ 200 to $ 1200, such a list will be several times larger. And if you add the list of center channel speakers, rear speakers and subwoofers, the tables of information grow to incredible volumes. You can, of course, solve all these problems in one fell swoop - large stores often sell ready-made sets of home theaters, complete with all the necessary components (often quite good). We are not talking about "theaters in one box", considering that true audiophiles, as they say, "prefer to suffer" and choose all the elements on their own. A cruel thought: should you always strive to purchase a set of cinema speakers made by the same company? It seems interesting to study the possibility of selecting individual elements of acoustics, especially if you, like the author, are completely indifferent (oh, horror!) To the color of the finish. It is possible that such an idea can give an excellent result. Without pretending to be the ultimate truth, let us try to give some controversial advice, which, however, more than once helped the author out. The purchase is preceded by a selection process that can be carried out at the initial stage using reference data.
Floor stand against shelf
No matter how they persuade us to buy neat bookshelf speakers, people are more willing to continue to choose floor-standing acoustics - as a rule, they have larger diameter speakers, a larger cabinet volume, and, consequently, deeper bass. It is noteworthy that, according to all the rules, shelf-type speakers must be installed on racks, so in the end they will take up as much space as floor stands, and the total costs (AC plus stands) will correspond to the cost of a floor system more than high class... If you are an audio specialist, then the allowable power that can be supplied to the acoustics and the sensitivity of the speakers should be considered together, given the size of the room. Other consumers can easily do without calculations: all modern hi-fi acoustics are ready to work in typical city apartments. If possible, pay attention to the speakers, which have a large mass and dimensions. However, this recommendation is of secondary importance, just as the specific material of the cone is not decisive (otherwise all speaker manufacturers would have used a single construction material long ago).
More stripes
Minimalist audiophiles will most likely prefer the classic two-way speaker (two speakers: a tweeter and a midrange / woofer), but if you decide to buy floor-standing speakers, it is better to look among them for 3- or so-called 2.5-way speakers, in which the woofers ranges are duplicated to reduce the operating offset of the diffusers (a common way to reduce THD). Opinion enthusiasts can see for themselves that the best professional monitor monitors and expensive high-end systems are often made in four or even five-way schemes. Those who want to check this fact can look at the summary table of acoustics parameters; the numbers in the "number of stripes" column tend to increase with the price. By the way, it is known that Prince Charles (probably together with the Queen of Great Britain) listens to five-way speakers ... This reasoning can be ignored in relation to rear speakers for home theater (they may well be two-way). The center channel acoustics must be very well shielded. This will save your picture tube TV from the appearance of color spots in the picture. The check is elementary: bring the speaker to the screen of a working TV.
Fewer options
Now you can create a table of preferred options, summarizing the data on the speaker models that suit the price, number of bands and impedance value. With a little bit of surprise, you will find that the list has become noticeably shorter. Arm yourself with a phone or find out the real prices for the selected models via the Internet. It turns out that some of the models are simply missing on the market, some can only be bought without listening, for example, with home delivery or by order with a prepayment. Of course, you shouldn't buy such speakers. It makes no sense to react to spells like: the same acoustics - in Mr. N. In your room, it may sound completely different. In general, in the field of audio, the personal preferences and subjectivity of your acquaintances are poor advisors.
Select by ear
As a result of the previous manipulations, the list will most likely be reduced to 3-5 models that you can start listening to. Arm yourself with a CD or DVD of music you know well, recorded in high quality, and bring along a test CD with a sweeping tone across the entire frequency range and a sine wave of 315 Hz (0 dB level). Visit the large audio showroom with at least two of your favorite speaker models. Note that, as a rule, high-quality amplifiers are used for demonstration in hi-fi salons. Next, the most difficult thing: ask to connect one speaker of the first model to the left channel of the amplifier, and one speaker of the second applicant to the right channel. In response to the seller's indignant statements that this is not done, take the meaningful look of a sophisticated specialist (it should work). As soon as the speakers start playing, you will immediately hear the difference in sound. Pay attention to the tonal balance (warm / cold), after which you can safely put a tick in your list. Do not forget to level the sound volume if necessary using the balance control (speakers different models sensitivity may vary) and ask to remove the grill grills from the bezels. If you are lucky, and there are more acoustics options from your list in the cabin, ask to replace the speaker that does not sound like a new one. In the same way, by connecting two different speakers at the same time to the left and right outputs of the amplifier, you can compare the speakers of the center channel, the rear speakers. Note that the proposed method is actually very far from being perfect. This is just a fairly quick selection of a “tasty” sound, a sound that should be liked by the most obvious tonal features (like the color of the cream that decorates the cake). Of course, a deeper assessment of such subtle things as the dynamic capabilities of the system, the ability of the speakers to reproduce spatial nuances in the sound picture, to draw the scene in terms of the depth and width of the panorama, of course, assumes classical listening to a stereo pair.
What to do if it was not immediately possible to determine your preferences by ear (for example, the tonal balance, the level of nonlinear distortion and the sensitivity of different speakers turned out to be very close)? Place a test CD with a sinusoidal tone of 315 Hz (0 dB level) in the player, turn the volume control down. The last note is especially important: if you spoil the acoustics with too strong a signal, the administration of the salon will hardly like it. Disconnect one of the amplifier channels, and then slowly and carefully add volume, listening to the character of the rather unpleasant humming sound. At some point, the sound will become distorted, as if buzzing. Record or memorize the corresponding level meter reading on the amplifier. Turn down the volume, then do the same trick with the other speaker. If the sensitivities of both applicants are close, then the speaker with the highest indicator has a better chance of being chosen, since it produces sound without distortion at a higher volume. It is not bad to supplement control listening with a sweep-tone jogging over the entire frequency range. There is no need to torment the speaker with a high volume: even a quiet sound is enough to assess whether there are any extraneous overtones, resonant bursts or inharmonic manifestations such as bounce of structural elements (plastic pads, grills, crossover boards, etc.). We emphasize once again that such an unusual way of comparison cannot be considered 100% correct, but everyone can be convinced of its effectiveness.
Finally ...
When buying acoustics hand-held or on the market, ask to connect a pair of speakers to the amplifier. At a moderate volume level, listen carefully to the operation of each speaker with your ear close to it. You should hear the performance clearly in the frequency bands from the topmost head to the bass. Gently place your fingertips on the edges of the woofer and midrange cones near the suspensions - you should feel a decrease in the vibration amplitude as you alternately “feel” the bass speaker and midrange driver. This effect will indicate that there is no short circuit in the crossover circuits. Attention! Never touch the dome membranes of high-frequency emitters - micron-thick metal and silk hemispheres are very easy to damage! At a decent volume, the air flow in the bass reflex tube is well felt. Press your palm firmly against the bass reflex opening and make sure that the sound has changed slightly. A decrease in the bass level indicates that the bass reflex tube is not accidentally blocked from the inside with damping material (a very common assembly defect). Of course, it would be nice to bring your own newly acquired amplifier and test it with different speakers, but not every salon will agree with your proposal. The best way out is to receive sets of acoustics on bail for testing at home. However, in our reality this option looks absolutely fantastic.
These guidelines are of course not exhaustive or binding. And yet ... Do not forget to test your system with the mentioned signal (315 Hz with 0 dB level), record somewhere in a conspicuous place the reading of the volume control on the amplifier corresponding to the beginning of distortion, and never exceed it. Remember, acoustics are afraid not of a loud signal, but of a distorted signal.
