Dancing on the site in front of the dacha, karaoke party with friends, listening to your favorite discs, children's party with games to the music - player and computer speakers clearly will not be enough. What if you have a large nice car and you are used to music that lifts your mood? The built-in subwoofer seems too primitive and does not provide the required quality. Everything is clear - you need to buy a separate device to amplify the power. Which audio amplifier is better? This will be discussed in our article.
What amplifiers are there?
Opening the catalog of audio equipment, you will be surprised to find that the amplifier is not the same. They differ in many ways:
- type;
- element base;
- the number of channels;
- power;
- distortion factor;
- minimum permissible load;
Type of
The type is determined by the functions that the device must perform. There are only three types:
- preliminary;
- terminal;
- full.
Preliminary
A preamplifier, as the name suggests, is designed to prepare a weak sound signal to gain. They put it next to the sound source. This arrangement is convenient as it avoids interference.
Preamplifier consists of several blocks:
- switching inputs;
- volume and tone control;
- the amplifier itself, which allows you to increase the signal power.
Important! The preamplifier is used in conjunction with the power amplifier.
Terminal
This is a power amplifier. But it is not only power that enhances this device. With its help, the signal is brought to the level. But it is impossible to adjust the signal parameters using such a device.
Full
It combines the functions of a preamp and a power amp. It is very convenient. As for the price, such a device will cost less than a set of preamplifier and finished amplifier.
What's inside him?
According to what elements are used, amplifiers are also divided into three types:
- lamp;
- transistor;
- hybrid.
On lamps
If you are thinking which amplifier is better, try to determine for what purpose you need it. Lamp technology has a lot of advantages:
- relatively simple scheme;
- high quality sound;
- good timbre of sounding;
- low noise level;
- soft limiting of the signal;
- overload resistance;
- ease of setup;
- resistance to power failures.
True music lovers often choose tube amplifiers. However, such devices have some disadvantages:
- high power consumption;
- heavy weight, because there are heavy transformers inside;
- an increase in power over 20 W requires a change in the circuit using scarce lamps.
Important! With the increase in power, weight and price inevitably increase.
Transistor devices
The operation of such amplifiers becomes possible thanks to the use of bipolar and field-effect transistors. The circuits of such devices are more complicated than lamp ones. The undoubted advantages include the relatively low cost and low weight. If we talk about the shortcomings, then they are:
- the need for additional protection of the output stages;
- the need to protect the power supply.
Important! Now, instead of discrete elements, such amplifiers are often used integrated circuits which are more compact and easy to repair.
Hybrids
Hybrid devices use both lamps and integrated circuits or transistors. Such amplifiers combine not only elements, but also the advantages and disadvantages of tube and transistor ones. There are a lot of options, so you can choose the sound amplifier that ideally suits your purposes.
If you try to determine the merits, you get a solid list:
- high quality sound and soft timbre, like a tube;
- relatively low weight;
- extensive price range;
- greater in comparison with transistor resistance to power failures.
How many channels do you need?
The number of channels depends entirely on the speaker system you are using. Usually there are from one to six of them, although hardware manufacturers are no longer limited to this - you can find devices with much big amount channels. The whole question is whether this is exactly what you need.
One channel device provides monaural sound, two channels provide stereo sound.
Important! The maximum quality is obtained if you follow the principle that the number of speakers and channels should be equal. Moreover, each speaker has its own personal channel, and each channel has its own column.
The amplifier for playing music must be at least two-channel in order to reproduce stereo sound. For a home theater, the minimum configuration is 5.1. But there may be more interesting options - there are also 9.2 configurations on sale. The number of channels is indicated in the documentation for the device.
Choosing the power
An amateur who decides to buy high-quality sound equipment is often lost - what to buy first, and then what? Professionals advise first of all to choose a speaker system, and then select an amplifier for it, depending on its configuration. This order is more convenient because:
- Matching an amplifier to an existing system is much easier than a system to an amplifier.
- The characteristics of the system can tell you how much power the amplifier should have.
To choose a sound amplifier for power, you need to take into account a few very simple considerations:
- Do not count on the most high quality sound will turn out to be at the limit of the power of the amplifier and speaker system. This almost never happens - the best sound is achieved at about 70-75% of the maximum power of the amplifier and about 90% of the system. That is, the amplifier should be about one and a half times more powerful than the rest of the equipment.
- You should not focus on the maximum value that is indicated in the certificates - you need to take into account the nominal, since it is this that provides the specified level of distortion and long-term sound reproduction.
- Also keep in mind the sensitivity of the speaker system, which is measured in decibels: when the sensitivity is reduced by 3 dB, but you want to get the same volume, the power of the amplifier needs to be doubled.
Distortion factor
In fact, it consists of two coefficients:
- intermodulation distortion;
- harmonic distortion.
They are expressed as a percentage. Modern high-quality equipment is most often made according to the DIN 45500 standard. According to this standard, the following distortion parameters are set:
- intermodulation - no more than 3%, frequency band - 250-8000 Hz;
- harmonic - no more than 1%, frequency band - 40-12500 Hz.
Minimum permissible load
The load impedance of the loudspeaker determines how much power the amplifier is needed. The smaller it is, the more power is needed. However, it is also important what minimum load the column can withstand and at the same time does not burn out.
Signal and noise
The sounds that come out of the amplifying device are not the same. The signal can be useful and noisy. Helpful - music or speech, for example. Noise - crackling and whistling, which sometimes makes the equipment.
Important! This parameter is expressed in decibels. A suitable value for household equipment is 90-100 dB.
It is generally accepted that the more expensive the equipment, the better it is. This is not necessarily the case. The price does not always determine the quality, but nevertheless, it must be borne in mind that a good device cannot be too cheap. Unless you buy it at a thrift store, where the most incredible accidents are possible.
You should not buy equipment where it cannot be tested. It makes sense to do this only in one case, if you have chosen a model in advance and trust the seller.
Important! Consider also what kind of area you will sound - the approximate power of each channel is calculated per 1 square meter. The best option is 3-5 W per 1 sq. m.
Subtleties of connection
Thinking about how to choose an amplifier, be sure to pay attention to the peculiarities of connecting to acoustics. Modern equipment has two types:
- on spring clips;
- at the terminals.
The second option is more convenient in all respects:
- the terminals hold the cables securely;
- the presence of such mounts indicates the high quality of the equipment.
Additional features
Almost all modern models have a built-in crossover. It is needed to cut low or high frequencies. In fact, it is a system of filters tuned to specific frequency components of the signal. It splits the signal into different frequency bands, directing them to acoustic radiators adapted for the given range.
In addition, modern amplifying equipment has a smooth control of the cutoff frequency. Many models are equipped with switches that allow you to multiply the frequency by 10, 100, etc. This makes it possible to amplify the signal in each channel without using an external crossover.
Important! If you have a high quality speaker system and don't need special effects like ultra-low bass, you won't need a crossover.
How to choose the right amplifier for your car?
In many cases, a built-in amplifier is sufficient for drivers. However, owners of high-end cars often strive to increase the sound power and install an additional speaker.
In this case, the weight of the equipment does not play a big role. Therefore, you can safely buy tube amplifier which gives the maximum sound quality.
As for the rest of the parameters, they can be as follows:
- it should be a hybrid - it takes up much less space than the preamplifier and power amplifier combined;
- power is calculated based on the value of 3 kW per 1 sq. m (5 kW - better for rooms, moreover, large);
- as in any other case, the amplifier must be suitable for the specific speaker system;
- connection with acoustics - using terminals;
- distortion factor - for high-end equipment.
Important! When buying, do not forget to look at the certificate, which must indicate the real power for specific device with a specific serial number.
Where to put it?
This is an important question as it affects the size of the device you choose. The amplifier can be supplied:
- on the back of the rear seat;
- under the seat;
- on the back shelf;
- to the underground
Home amplifier
Houses can be placed and hybrid device, and two separate - it all depends on the size of the room. The power is also considered from the area:
- if the area is less than 15 sq. m, power is calculated from 3 kW;
- if more than 20 square meters - you need to take the number 5.
Important! In this case, it is worth taking care that the signal level at maximum values does not exceed the pain threshold, otherwise the music will be harmful.
Other characteristics:
- An important point is distortion. They should be minimal.
- And here frequency range the maximum is needed, then the sound quality will be high.
- As for the number of channels, the options may be different. Of course, nowadays there are not so many fans of monophonic sound, so a single-channel device is unlikely to suit you.
- Ideal for home - universal device capable of providing good sound and when listening to audio recordings, and when dubbing films.
Now we have figured out all the intricacies of this seemingly difficult task. We hope that you could easily figure out which sound amplifier is better and are not disappointed in the resulting quality.
... So, you've finally decided to listen to music on something better than a boombox or a stereo system. In this case, you will have to assemble a so-called component audio system at home, that is, a sound complex consisting of separate devices. In addition to the amplifier and acoustic systems, this complex will include signal sources - devices from which sound is reproduced.
Text: Anatoly VEITSENFELD, sound engineer
Most often it is a CD player and a tuner (radio receiver), but experienced amateurs may also have players vinyl records, as well as tape recorders or mini-disc recorders. Video equipment also belongs to the sources of audio signal - both outdated analog video recorders, as well as current DVD and Bluray players. Modern digital devices such as media players, smartphone docks, or Internet media servers are all audio sources, just like computers. But quite often they play synthesizers at home, sing karaoke, etc.
The signals from all of these such different devices will end up in your speakers, but for that they have to go through the heart of your sound complex - the amplifier. Let's talk about amplifiers.
There are quite a few types and varieties of amplifiers, so you must first classify them, and then deal with their functions and capabilities.
Preamplifier
The level of the electrical signal at its output is such that if it is fed to the loudspeakers, we will not hear anything. So what is it for?
First of all, for commutation. All of the above sources are connected to the preamplifier in the optimal mode for each of them.
The fact is that different sources have different output signal levels: a CD player or a tuner outputs a signal of the so-called. linear level (on the order of a half-volt), and a vinyl turntable is many hundreds of times less.
In addition, the user should be able to switch sources, and they should sound at approximately the same volume. This requires matching the signal levels of different sources and raising them to a level that is sufficient for the operation of the input stage of the power amplifier.
Another function of the preamplifier is the organization and switching of the so-called. end-to-end channels, i.e. while listening, it is also possible to record a signal on a particular recorder, including carrying out these two processes independently.
Another important function is adjusting the output volume and frequency equalization of the signal, for which there are volume and high and high level controls on the front panel. low frequencies... Often there is also a direct signal button, i.e. bypass frequency equalizer, and the so-called loudness button, designed to raise the low and high frequencies when listening at reduced volume. The preamplifier can also have an additional infra-low pass filter, which is especially useful when using a turntable.
On the rear panel of the preamplifier there are input jacks for connecting sources, usually there are 5-6 of them and they are made according to the so-called. unbalanced circuit for connecting RCA connectors (commonly called "tulips"), there are also output jacks. Usually there are two of them - the main one for connecting to a power amplifier and an additional one for recording. On some expensive models, there are also so-called. balanced XLR type connections commonly used in professional equipment. Their main advantage is the ability to transmit a weak signal without interference over a very large, tens of meters, distance - for ordinary home listening this is of little importance, so there is no reason to overpay for a function that you most likely will not use.
Almost all modern amplifiers have the ability remote control volume and switching sources, they can often be used to control some functions of other devices of the same company, for example, turning on the playback of a CD player, etc. one firm. It should be noted that separate amplification, i.e. a pre-amplifier and a power amplifier are an expensive solution, since the cost of each of them starts from 20 thousand rubles.
Power amplifier, sometimes called terminal
Functionally, it is very simple - it has one input, usually stereo (otherwise, two mono amplifier), and of the controls, often only the volume knob. But with the simplicity of the functionality, this is a very serious device, and therefore it costs more than a "fancy" preamplifier. High sound quality is ensured through the use of powerful heavy transformers and high-capacity capacitors capable of high level output the input signal to the load, i.e. loudspeakers, very high current. That's why good amplifier- always heavy.
For the power amplifier, the nominal load value is important, i.e. speaker impedance. Typically amplifiers are rated for 4 or 8 ohm speaker impedance. You can connect acoustics with higher impedance to the amplifier, but in no case with less! This can damage the output stage under certain conditions!
Another important parameter is the slew rate of the output voltage. The faster this speed (measured in microseconds), the better amplifier reproduces the so-called. transient, or "non-stationary" processes, i.e. small fast high frequency signal components. For example, playing cymbals, percussion, plucked string instruments, etc. It is clear that a "slow" amplifier will not work well for such sounds and will blur the sound picture.
Integrated or full amplifier
It is the most popular device on the market that combines a preamplifier and a power amplifier in one package. All the functions described above and the features of each of the constituent parts are present in the integrated amplifier. Quite decent full amplifiers are available to almost everyone, their cost starts from about 8000 rubles.
If you are not going to experiment with the selection and frequent replacement of components in your audio system, an integrated amplifier is a smarter purchase, but if you are planning a gradual upgrade of your kit to a higher class, separate pre and post-amplification is more suitable for you.
Receiver
This is a versatile device, a kind of combine - an integrated amplifier, which also has a built-in radio receiver (tuner), and often also a digital signal effects processor.
These effects include a multi-band equalizer, reverb, and in the case of a Surround receiver, also a decoder for Dolby Digital multichannel phonograms. Moreover, such a device may also have microphone inputs for karaoke, and the latest models also have an Internet radio receiver and an Ethernet port for connecting to a network.
If you are looking for an all-in-one device, then this receiver is for you. But you need to take into account that miracles do not happen, and the price of a good universal device should correspond to the cost of the components. If a sophisticated multifunctional device costs like a simple amplifier, it means that the developers have seriously saved on components and circuitry.
Choosing an amplifier
This issue has already been partially touched upon in the description of the types of amplifiers. Now let's go a little deeper into it.
Should I listen to the amplifier in the store?
If possible, then yes. Another thing is that the practical value of such listening is not great - a lot of different factors, both technical and psychological, will affect your perception.
For an accurate subjective assessment of the sound, you need to have a lot of experience and a trained ear. It should also be taken into account that modern equipment of the same class (i.e. cost) sounds almost identical, with minimal difference, so there is a danger of falling into self-deception, or even deception on the part of those who want to sell you equipment.
In any case, in the store, listen to the sound "in a first approximation": how the amplifier sounds at a very quiet volume, at a very high volume, how effectively (deeply) the treble / bass tone and tone compensation controls work, whether the self-noise level is high when setting the volume control to the maximum when the source is off, whether the volume changes smoothly when you turn the control. This will allow you to generally understand whether the device is right for you.
Tube or semiconductor?
This is an important question, but for those who value sound quality more than the average music lover. Many connoisseurs value the lamp for its comfortable sound, but not everyone can grasp these nuances, and not everyone sets themselves the task of savoring purely acoustic features instead of just listening to their favorite music.
In addition, tube amplifiers have not only advantages, but also known disadvantages. In terms of such parameters as the signal-to-noise ratio and the coefficient of nonlinear distortion, tube amplifiers are noticeably inferior to transistor ones. They produce much lower output power (although, I note, the power of the lamp and the power of the transistor are not the same). Tube amplifiers have much lower energy efficiency, i.e. at low sound power they consume electricity "with all their hearts".
Lamp technology in everyday life is more capricious, and handling it requires preparation and care, including in terms of safety. Finally, tube amplifiers are more expensive than semiconductor ones: a "sensible" tube power amplifier is cheaper than 70 thousand rubles. not to be found, and an integrated tube amplifier with a power of at least 40 W starts from 40 thousand rubles. In short, a tube amplifier is not for beginners, but for sophisticated connoisseurs.
How to match speakers and amplifier?
It should be borne in mind here that an amplifier, even an inexpensive one, is a less critical component of the audio path than a speaker, and in general it creates less problems in sound than loudspeakers.
So if you already have speakers that suit you, be guided by the following factors when choosing an amplifier:
The nominal load impedance of the amplifier should correspond to the impedance of the speaker - if you have speakers with a resistance of 4 Ohm, you must also select an amplifier designed for a load of 4 Ohm or more.
The output power of the amplifier should not exceed the rated power of the speaker systems, it is better that the speakers are a little more powerful than an amplifier this will save them from damage if the amplifier is accidentally turned on at full volume.
If your speakers generally suit you, but you still think that they almost lack the highs or lows, inquire about the quality of the tone controls on the amplifier: very often it is enough to raise the highs or lows with the existing two-band equalizer. If this is not enough, then nothing can be done, you will have to change the speakers.
How to choose the components in the complex?
We must not forget that all components in your complex must be of the same class in terms of price and quality. Too cheap will equalize the advantages of more expensive ones, but too expensive, on the contrary, will not sound in full force.
However, if you bought it "for growth" and are going to bring other components to it over time, having received a system of a higher class, buying an expensive component may make sense. This is especially true for loudspeakers. But this is a completely different topic ...
It is now very widely believed that hi-fi equipment released in the 70s, 80s and early 90s is a priori of high quality and that it is possible to build a sounding "vintage" audio system from these used audio components without significant costs. , similar in quality to much more expensive modern ones.
Let's try to understand this theory. There is some truth here - the very dawn of the sound industry fell on the above period of time. Turntables and correctors for vinyl playback, magnetic recording devices have reached perfection, digital sources have appeared, a lot of models of really high-quality power amplifiers have been produced. Everything is true, but there are nuances :)
There was no official division of equipment into Hi-Fi and High End at that time, however, in fact, there were both budget components and very expensive ones. If you do not take into account the most budgetary and most exclusive models, and somehow highlight the conditional middle class, then the range of prices is still impressive: $ 300-2500 per component. And if you take into account that $ 2,500 in the mid-80s is just a lot of money, it becomes clear that nothing has changed since then - high-quality sound, as it was expensive then, is so expensive now.
With the advent of online auctions, used equipment of Japanese and European production flooded in a huge stream to search for new owners, and a significant part of it went to us, to Russia. At first, for a very low price, a lot of exclusive and initially expensive equipment was exhibited at auctions, but this did not last long, the market put everything in its place - the owners, getting rid of unnecessary equipment for symbolic money, were massively replaced by dealers seeking to make good money on this. And the owners themselves quickly figured out what and how much.
As a result, the cost of budget components became such that, in order to maintain stable demand, it became necessary to form a new understanding of vintage among consumers, that is, to present consumer goods of those years as an equivalent to modern high-end audio components. I must say that progress in this area has been achieved, and considerable, the concept of "vintage", which used to mean expensive and high-quality components in excellent technical and cosmetic condition, now for most means any budget junk 30-40 years old. It's sad but true. Of course, the real vintage has not gone anywhere and is also presented on the market, but it is affordable for very few.
What is the difference between the budget and high-end components of the golden era of audio? In principle, everyone. This is a different level of installed components, materials used, quality of circuitry, etc. For example, consider two amplifiers of the 80s of different price categories: the very popular "vintage" amplifier Dual CV-1460, which cost about $ 400 at one time, and the much more expensive two-unit Onkyo Integra P-308 preamp + Onkyo Integra M-508 power amplifier ($ 800 + $ 1500, respectively). All these devices are not rare and are often found in the vastness of online auctions and from owners of audio equipment.
Amplifier Dual CV-1460
If you believe what is written about this handsome man in Runet, then when you buy a Dual CV-1460, you become the owner of a “legendary” product operating in “pure class A”, with a high output power (2x95 W at a load of 8 ohms) and providing "Exceptional sound quality" equipped with an "excellent" vinyl equalizer. Now let's look under the lid, turn on the devices, and listen.
Integrated Amplifier Dual CV-1460 Opening ... We see an absolutely budgetary design with a complete set of the level of a music center - cheap potentiometers, spring-loaded connectors for speakers, etc. There is not even an AC protection unit - a 3.15 A fuse is included in the sound circuit instead - that is, if the final stage burns out and a constant voltage appears at the output of the PA, the ACs will remain intact if the fuse has time to burn out before the woofer coil. Great, this is encouraging :)
Integrated amplifier Dual CV-1460 with the top cover removed Upon further study of the design, some doubts arose regarding the correspondence of the reality of some of the declared parameters - the amplifier indicated in the passport long-term output power "long" will not withstand. There are two reasons:
1. Fuse in the AC connection circuit with a rating of 3.15 A, which corresponds to a maximum output power of 80 W at an AC 8 Ohm. If you use an AC 4 Ohm, then the fuses burn out, approximately at half the power.
2. Standard cooling radiators may not cope with dissipating the required amount of heat - their total area is too small.
We deal with the "class A". Naturally, a specialist immediately understands that an amplifier with such dimensions and weight cannot work "in pure class A", because an amplifier with an output power of 95 W per channel must dissipate about 1 kW into heat in this case. We check the quiescent current setting according to the service manual, measure it and see that it is as much as 3 mA! The amplifier actually works practically in class B, that is, "Dual class A", this is the name of another circuitry trick that makes the transistors of the final stage work without switching distortions at a very low quiescent current, that's all. A similar circuit design, called "New class A", is used in Technics amplifiers. It seems that there is no deception, but there is no class A either - it is very well thought out.
Further, we listen to this "legendary" amplifier - the sound is rather soft, does not irritate the ear, but the overall musical resolution is very modest, the stage is there, but it is flat, slightly wider than the speaker. He does not make porridge on complex compositions, but “cuts off” all that is superfluous that prevents him from adequately reproducing a musical fragment. The microdynamics are simplified, the sound is generally poor. The "fine" built-in vinyl equalizer sounds nothing at all, which is not surprising for a single-op amp circuit with a RIAA equalization circuit in feedback.
In general, nothing outstanding is standard for a budget device of all times. You can listen to music on this, of course, but there can be no question of any high quality sound and speech.
Onkyo Integra P-308 and Onkyo Integra M-508 Kit (200W / 8 ohms, 290W / 4 ohms)
These are not the top models of this series, there is also the P-309 + M-509, with a total cost of $ 6,000 (in the 80s) and a total of 41 kg in weight, but I will write about those that I researched and listened to personally.
Onkyo Integra P-308 Preamplifier and Onkyo Integra M-508 Power Amplifier This two-block unit is equipped quite well - a double mono design, including separate mains transformers, an energy-intensive power supply unit, three pairs of output transistors in the end stages of each channel, with a total quiescent current of 300 mA (class AB). The photo shows that the equipment and construction of the Onkyo Integra P-308 \ M-508 is seriously different from the budget Dual CV-1460. You don't need to be an expert to understand this, so I will not go further into technical details and go straight to listening:
The sound is soft, uncolored, the device builds a sufficiently deep stage that goes beyond the speaker placement, the sound is not tied to the speakers, the UM sounds emotional and has a high musical resolution. When the volume is increased, small details are not lost. This amplifier does not tire the ear at all, you want to listen to it.
Yes, the Onkyo Integra P-308 \ M-508 is a good amplifier, although it does not belong to the highest category - it is a solid middle class. Naturally, there are more worthy models. Somewhere from this level, from my point of view, really "vintage" begins.
Onkyo Integra M-508 Power Amplifier with Top Cover Removed 
Onkyo Integra P-308 Preamplifier with Top Cover Removed But in full measure, it is possible to call this only devices that are also in an impeccable technical and cosmetic condition, which, alas, practically does not exist at auction. Most of the vintages require not just repairs, but rather technical restoration, and every year the situation is steadily worsening (an excellent external condition is still quite possible to find). This is where a new problem is revealed - how much the equipment you have chosen has suffered from the time and storage conditions of the previous owner.
Very often, based on the internal state of blocks and assemblies, one can make an unambiguous conclusion that the device has been stored for more than one year in an unheated room, such as a garage, basement or balcony. Note that if there are traces of corrosion on the case or the internal chassis of the amplifier or blackened soldering on the boards is visible, then you should not contact the purchase, definitely. In the best case, the restoration will cost much more, in the worst case, the amplifier may not be repairable.
If there is a desire to purchase a device that will delight with sound for a long time, and not regularly spoil the mood with a failure or endless minor refusals and flaws, then you must first make a successful purchase from an auction (the condition may be worse than the declared one), and then find a qualified specialist who will bring your new audio component to the required technical state. This is an expensive procedure, there are not very many such specialists, to put it mildly.
But there is a lot of equipment that is already on sale in Russia with the note: "Preventive maintenance and adjustment of all modes by devices, in accordance with the original service manual, has been carried out." As practice shows, the percentage of really carefully restored and tuned vintage devices for sale is quite small. Therefore, you should not hope for this. The reason is simple - it is a laborious and expensive procedure that significantly increases the cost of the product and which does not make sense to carry out if the audio is purchased at an auction for resale. Usually, all such "prevention" comes down to banal lubrication of the regulators and switches so that they do not emit loud rustles and clicks in the speaker during the show to potential customers. That is, the minimum necessary actions are performed, which do not require time-consuming study of the service manual, disassembly of units, measurements, etc.
It is worth noting, perhaps, that not all, including the top-end amplifiers of the past years, initially had an excellent sound. There have been plenty of unsuccessful, bad-sounding amps. An example is the Revox B-251.
Integrated amplifier Revox B-251 This amplifier has a powerful switching power supply on board, digital controls for volume and input sensitivity, and electronic commutation. As a result, the sound is clear, transparent, but completely lifeless, tiring. The picture is flat, there is no stage at all, the sound is tied to the speaker. The parameters, however, are quite high. A friend of mine bought himself a Revox B-251 with only one purpose - the rack of Revox components does not look without it, and he could not find anything else in design.
It also happens the other way around, of course - the integrated amplifier Technics SU-V10 (not to be confused with the V10X - this is a completely different amplifier), which cost $ 900 in 1982, is in no way inferior, and in some ways even surpasses the two-unit monster Onkyo Integra.
Integrated amplifier Technics SU-V10 
Technics SU-V10 Integrated Amplifier with Top Cover Removed But this Technics model is almost impossible to find in fair condition and to buy. In general, if you plunge headlong into the world of vintage auctions, you will soon notice that certain models are valued much higher than others and go under the hammer as soon as they appear in the ads on the relevant sites. The reasons may be different - some sound good, others are easy to repair, others are collectible rarities, etc.
To summarize the above, the conclusion is this: a really high-quality vintage amplifier, which is in excellent technical and cosmetic condition, tuned by a qualified specialist, according to service documentation, may well compete with modern devices of a high price category, but its resulting cost will be considerable, maybe even be comparable. And budget amplifiers of those years can successfully compete only with their modern classmates. Their main advantage over the remake is the absence of electronic commutations and adjustments, which, as a rule, have a detrimental effect on the sound, with which almost all new PAs are now simply stuffed.
The article contains my personal opinion, based on many years of practical experience, but it may not coincide with the opinions of other people and I don't see anything wrong with that.
First publication of this article
Best regards, O. Shamankov ( Prophetmaster)
