Who doesn’t remember the famous S-90 speakers from the 70s? (In fact, there was a Latin letter S, and therefore this Riga product was called the Radiotehnika S-90 speaker system, but the habit of not trusting anything foreign also came from this time, and then not everyone knew that the Balts use the Latin alphabet.) Dance regulars in the club (called discos in the 80s) they didn’t go into such details, and therefore they still call these speakers S-90. This article will be devoted to the literally legendary acoustics of Soviet times.
Nostalgia
"Radio Engineering S-90" was considered one of the best systems of that time and was in demand everywhere. Concerts in cultural centers in the most remote corners of our country, amateur performances, school evenings with songs and dances - everywhere this equipment was indispensable. Some irresponsible comrades risked conducting rehearsals at home, and the S-90 speakers created an unforgettable sound effect in absolutely all apartments of the five-story panel building. The “gratitude” of the neighbors was also indescribable. They can be understood. Even if the owner “turned up” the medium volume, extraneous sounds simply evaporated: the howling of dogs, the knocking of neighbors on the radiators, as well as the sound of sluggish bass from ordinary speakers two floors above disappeared.
The “Radio Engineering” column heralded either an approaching earthquake or a military fighter jet touching the roof in a low-level flight. The chandeliers bounced, the crystal in the sideboards tinkled subtly, and everything in the room that was not secured was clearly vibrating. Although it must be said that the S-90 speakers were not and were not considered the most powerful in their class, an amplifier was installed to them. By the way, working versions of this equipment are in great demand today. Even heavily used retro equipment is quite expensive. A “Radio Engineering” column of any modification in working condition will cost from four thousand rubles. One!
Description
The Radiotekhnika acoustic system of the highest (zero) class 35 AC-1 went on sale in 1977 and was immediately named S-90. The speakers had the best characteristics for those times, especially considering that only Soviet equipment was used. They were developed purely for domestic use, and this was done by the Orbita design bureau at the Riga Radio Engineering Production Association. Subsequently, the entire series of these acoustic systems received the S-90 brand.
The speakers fully justified their characteristics; they were in no way inferior to imported ones, significantly surpassing all domestic ones. In order for the sound of the acoustic system to be complete, an amplifier of the “Electronics” or “Amphiton” type must be connected to it. In the frequency range from 31.5 to almost 20 kHz, the speakers operated with a nominal power of 35 Watts. Moreover, the power in the passport was ninety. The sound pressure, the results of which are described above, was 1.2 Pa.
About the disadvantages
The weight of one column sometimes exceeded thirty kilograms. They cost three hundred rubles per pair (an engineer earned from ninety to one hundred and twenty rubles a month). However, few have seen them on sale for free. Many people bought S-90 music speakers one at a time, despite the fact that there was no guarantee that buying a second one would make them a well-tuned pair. However, even if a pair was purchased, no one guaranteed its balance: for example, the right speaker of the S-90 collected all its power together and persistently sounded louder than the left. This is despite the fact that the equipment was positioned as having the highest category of quality.
This drawback is not the only one that the S-90 column could have. Tweeters often failed because the thin and weak wires themselves were not very practical. At mid frequencies the sound was downright bad and often spoiled the whole impression. Other electronics could not withstand the sound system next to these huge structures, and the magnetic field created by the speakers had a negative effect on humans. And yet, it was the S-90 that could ideally create surround sound in an ordinary apartment of a standard panel house. In general, there were no special complaints about the sound.
Installation
The shortcomings that the Soviet S-90 speakers had did not stop music lovers throughout Rus'. For several decades they remained one of the most popular acoustic systems. Many thousands of pages on forums are dedicated to them today. This is one of the most striking symbols of a bygone era, which also had reliability and durability, which modern gadgets do not have at all. The S-90 speakers had impressive dimensions (36 x 71 x 28.5 cm), so they required proper installation, which was not always combined with the capabilities.
The apartments were quite cramped (and the conditions are the same now), and therefore you could see the speakers half a meter from the listener. While the ideal way for better sound is to place them on a pedestal just half a meter high and maintain a distance of at least two meters from the listener’s ear. Rarely does a room have such advantages; most often the required space is not enough, and therefore only the neighbors listened to the real sound that this equipment was capable of.
Appearance
The S-90 speaker has a simple and well-made body - a non-separable rectangular box made of chipboard, trimmed with high-quality veneer from valuable wood. The wall thickness is sixteen millimeters, and the front panel is made of twenty-two millimeter aircraft multilayer plywood. The joints of the walls and internal sides are reinforced with special elements that increase the rigidity and strength of the body.
The heads have decorative black frames stamped from aluminum sheet. They are also protected by a metal mesh. On the front panel, the mid-frequency head is insulated inside with a cone-shaped plastic casing, the low-frequency head is located along the vertical axis. At the bottom of the column there is an overhead plastic panel with a nameplate. There is also a hole 100 x 80 millimeters - this is the bass reflex output. The amplitude-frequency response (AFC) is displayed on the nameplate, all curves correspond to the positions of the regulators. There is also the name of the speaker system and the brand name. The above-described frame with fabric is attached to the front panel with bushings. On the bottom rear wall there is a block with terminals.
Inside
The internal volume is filled with a sound absorber made of technical cotton wool, covered with gauze. In this way, the influence of sound pressure on the frequency response is reduced and a better sound quality of the speaker is achieved by eliminating resonances in the internal volume. Inside the case there are electrical filters on the board that separate the strips of the speaker system. The kit also included four plastic feet designed to be attached to the base of the cabinet, as well as a decorative removable frame with knitted fabric that adds acoustic transparency.
A rare acoustic system of those times has such qualities as the S-90 speakers - the sound power is simply off the charts! But at close to the maximum volume, low frequencies become inaudible and booming, and the highs begin to click - this is a characteristic feature of the 6GDV-1-16 high-frequency drivers. A little later, when similar products began to go on sale - “Amfiton 35AS-018”, “Orbita 35AS-016” and others, a different head was used. Sometimes analogues of this speaker system provided a deeper and more balanced sound than the original S-90 speakers.
S-90 line
All modifications of the S-90 and even all its analogues were certainly aimed at using cassettes. The high-frequency head reproduces sound quite well in the upper frequency range thanks to the cassette deck and Soviet amplifier. But if the lower and middle parts of the high frequency range are reproduced just fine, then the very top is different from them, and therefore receives criticism for allegedly blocking the frequency response and unevenness.
And the “Orbita” column of the S-90 line from the Moscow plant turned out to be a truly worthy alternative to the Riga “Radiotekhnika”. This modification with a similar set of acoustic heads differed only in the presence of a two-tube bass reflex at the very bottom of the body. As a result, the bass became lower and thicker. However, at high power, problems with hum and inaudibility persisted, and the upper frequencies clattered in exactly the same way as with the Radiotekhnika S-90.
Manual upgrade
Many music lovers finally realized their own dream: they bought the legendary S-90 speakers and began to modify them with a file. The solution is budget-friendly, exciting, and then the sound is the envy of everyone. Over the past thirty years, the outside of the speakers, of course, has lost its former chic in almost a hundred percent of cases, but the main thing here is that no one messes with the inside. You need to start working by enriching your arsenal with tools. You will need a basic set of screwdrivers, pliers, and a soldering iron. The first step is to remove the front panel, for which you need to unscrew a dozen or two different screws.
When disassembling, it is necessary to check whether the filling corresponds to the passport. So that at high frequencies it would be 10GD-35, at medium frequencies - 15GD-11A, and at low frequencies, for example, 35GD (well, or whatever is stated in the passport). Speakers are most often damaged, since it is possible to destroy equipment within one day, and even more so in thirty years. For example, a lot of furniture rearrangements and moves could happen. Most likely something is damaged. For example, a woofer. Resuscitating him will require additional work. You need to rewind the reel. In principle, this is not so difficult if you know some of the subtleties and have encountered the rewinding process at least several times before. After winding, centering and drying, the sound of the speaker will be perfect - all extraneous sounds will disappear.
Domes
S-90 speakers, as everyone knows, most often disappoint with the sound of high frequencies - with overtones. And at mid frequencies there is often no ringing. Craftsmen recommend basically the same thing: replace the midrange, treble and dampen the body. But it’s better not to look for easy ways. The speakers are simply covered with plastic domes. This material is completely unsuitable.
Silk domes will remove overtones and make the sound more transparent. Therefore, the speakers can be safely replaced. While one speaker is being upgraded, it is necessary to test the sound and compare it with the one that is just waiting for the upgrade, that is, with the original one. Then it becomes absolutely clear whether to leave the rework or return everything as it was. The main thing is that the owner of the speakers and golden hands also has good hearing.
Wiring and housing
To improve the sound of low frequencies, the housing needs to be modified. Down with cotton gauze mattresses! Stores sell inexpensive batting that makes an excellent filling pad. And for just over a hundred rubles! All this can be done quickly and without any effort: the width of the batting is two meters, enough for two columns, but you will need a furniture stapler or a friend who has one. Before installation, just in case, it is better to change all the wiring and remove the switches. Cut out the batting in two layers and boldly sheathe the body.
The bass reflex pipe is placed on the sealant, and after that it is also covered with batting. There is also not much work to do directly with the filter. The switches will never be needed, so they can be removed, like all unnecessary elements from the board. Replace all these thirty-year-old thin wires with normal copper ones at all connections. Next, the filter, freed from everything unnecessary, must be carefully installed in the housing and covered with batting. The entire midrange box on the outside should also go under the material mentioned above.
Results
Judging by the reviews of home craftsmen, such simple modifications have changed the sound of the equipment for the better simply beyond words. The bass became clear, the top became transparent and light. After replacing the speaker, the vocals sounded completely different in the midrange.
Manufacturer: PA "Radio Engineering", Riga.
Purpose and scope : for high-quality reproduction of music and speech programs in stationary living conditions. The S-90 acoustic system, developed in 1975, is the first domestic system that meets the requirements of international documents for Hi-Fi equipment. Later models of this speaker “S-90B” and “S-90D” are distinguished by an expanded range of reproduced frequencies. Introducing an indication of electrical overload of loudspeakers and a new appearance. The recommended power of a high-quality household amplifier is 20 - 90 W. 35 AS-212 “S-90” and 35 AS-012 “S-90”, similar to AS, the difference lies in GOST.
Characteristics
3-way floorstanding speaker with bass reflex
Frequency range: 25 (-15 dB) – 25000 Hz
Frequency response unevenness in the range 100 – 8000 Hz: ±4 dB
Sensitivity: 85 dB (0.338 Pa/√W)
Directivity at angles of 25±5° in the horizontal plane and 7±2.5° in the vertical plane, from the frequency response measured along the acoustic axis of the speaker:
in the vertical plane: ±8°
horizontal: ±6°
Harmonic distortion of speakers at a sound pressure level of 90 dB at frequencies:
250 – 1000 Hz: 2%
1000 – 2000 Hz: 1.5%
2000 – 6300 Hz: 1%
Resistance: 4 ohms
Minimum impedance value: 3.2 ohms
Rated power: 35W
Maximum (nameplate) power: 90 W
Short-term power: 600 W
Weight: 23 kg
Dimensions (HxWxD): 710x360x285 mm
Installed speakers:
LF:
MF:
HF:
Design
The body is made in the form of a rectangular non-separable box made of chipboard, veneered with valuable wood veneer. The wall thickness is 16 mm, the front panel is plywood 22 mm thick. At the joints of the housing walls, elements are installed on the inside that increase the strength and rigidity of the housing.
The heads are each framed with decorative black plates, made by stamping from aluminum sheet, with four mounting holes. The midrange head is isolated on the inside from the total volume of the housing by a special plastic casing in the shape of a truncated cone. The LF head is located on the front panel along a vertical axis, and the MF and HF heads are shifted relative to this axis to the left and right. On the front panel there are also knobs for adjusting the midrange and treble levels, and in the lower part there is a plastic overlay panel with a nameplate and a rectangular hole 100X80 mm, which is the bass reflex output. The nameplate shows frequency response curves corresponding to various positions of the level controls, as well as the name of the speaker and the manufacturer's logo. In addition, the front panel has bushings for attaching a decorative frame with fabric. On the back wall, in the lower part, a block with terminals is attached. Each head on the front panel side is protected by a blackened metal mesh.
The internal volume of the speaker is 45 liters. To reduce the influence on the frequency response of sound pressure and the sound quality of the speaker resonances of the internal volume of the housing, it is filled with a sound absorber, which is mats of technical wool, covered with gauze.
Inside the case, on one board, there are electrical filters that ensure separation of the speaker bands. The crossover frequencies between LF/MF are 750±50 Hz, between MF/HF – 5000±500 Hz. The design of the filters and the overload indication unit uses resistors such as BC, MLT, SP3-38B, S5-35I, PPB, capacitors such as MBGO-2, K50-12, K75-11 and inductors on plastic cast frames.
The package included: four plastic feet that can be attached to the base of the case; removable decorative frame, covered with knitted fabric with high acoustic transparency.
It all started when a good old friend brought me speakers for my last birthday (October) - a legend from the times of the Soviet Union. We turned it on, listened, took it apart and realized that the legend was strong, but pretty tattered. It was decided to “refresh” the speakers, improve their sound quality while maintaining the “vintage style”. Now I am interested in modern trends of electronic music and its sound on these copies was completely inadequate. The work only began to come to an end in November of this year. The housing was modified, the bass reflex was recalculated and changed, the HF and midrange heads were replaced, and the crossover filter was completely recalculated. The appearance of the speakers has also undergone some changes.1. Brief description of the available S90D Speakers.
The S90D copies that were brought in, as I remember now, I couldn’t wait to quickly connect and listen to “Legend”. We listened to several discs with diverse music, unfortunately our expectations were not met, there was a fair amount of muttering and rattling of body elements, a screaming middle, and ear-piercing highs. Adjustment with MF - HF potentiometers (in this model they are located on the front panel and provide for smooth adjustment) did not give positive results.
A schematic diagram of these speakers was found on the Internet and they were disassembled and analyzed.
Judging by the burnt-out elements on the overload control board (the LEDs should light up when overloaded) and adjustments, as well as the deformation of the plastic frame of the crossover HF coil from the high temperature, it was clear that the life of the speakers was not easy. The speaker windings immediately raised concerns.
It turned out that judging by the dates of manufacture and types of speakers, there were no “original” speakers left in any of the speakers. All speakers except the HF were of a similar model - quite fresh and in good condition LF: 75-GDN-1-8, MF: 20 GDS-1-16, and HF instead of 6 GDV 6-25 there was an Alphard TW401 8 Ohm instead of the required 25 Ohms , but no changes were noticed in the filter. The sound-absorbing filler in the housing was approximately 3 liters in volume. The glass under the midrange speaker contains 0.2 liters. The crossover is made on a plywood board with hinged mounting. Crossover coils on plastic frames, paper capacitors.
2. The concept of the changes being made, the tools used, components and materials purchased.
The main idea before starting work was to bring the sound quality to an acceptable level, according to the cumulative assessment of the amplitude-frequency response of the phase-frequency response in the modeling program, our own tactile assessment of the sound and the assessment of familiar music lovers. The criterion was also the possible preservation of elements of the “vintage” style of the speakers, both externally and in terms of the element base.
Having searched and analyzed information on the existing heads, it was decided to leave the existing non-standard HF heads and standard LF heads. The existing midrange head, due to its too specific sound and not for the better, was replaced with a Visaton SC-13, which has sufficient purity and expressiveness of sound.
The design and location of the bass reflex have been changed; the location was chosen based on the prototype of speakers from similar times of approximately the same standard size from Sony.
It was decided to make a new crossover using the existing standard element base on the existing plywood board as much as possible.
The following software products were used during the work.
1. LSP Cad 2.5 simulation program
2. Program for calculating inductors E.S.P.G. -DOS
3. MAA audio frequency generator using a PC sound card.
Were purchased:
1. Book “Amateur Loudspeakers” by S. Bat (Audiomania)
2. Visaton SC13 midrange heads - 2 pcs (Audiomania)
3. Sound-absorbing filler (sitepon) - 1 pack. (Audiomania)
4. Woolen felt 5mm - 3 kg. (Wool factory)
5. Automotive carpet (finishing the front panel) - 3 sq. m. (Auto parts)
6. Carpet glue. -1 pack (Auto parts)
7. PVA adhesives - 1 l. (Construction market)
8. Capacitors, resistors. (Radio market)
3. Filter and bass reflex, as S. Dad writes about, the year the crossover was configured.
First of all, it was necessary to refresh my memory of the theory of filters from my studies at the institute; a number of information was found on the Internet, some of the information was gleaned from the purchased book by S. Bat.
In the course of analyzing the theory, the characteristics of the heads (HF and MF play quite well in the area of applying the frequency response of first-order filters) and numerous test connections, an approximate representation of the structure of the future crossover was born:
High-pass filter - 1st order,
Midrange filter - 1st order,
Low pass filter - 2nd order.
It remains to figure out the matching of filters by phase response, calculation by cutoff frequencies and calculation of attenuators.
The fascination with the theory was so detailed that in S. Bat’s book some errors were found regarding the polarity of the heads in one of the circuits published in the book, as a result of which he entered into a fruitful correspondence with the author of the book on this subject and with wishes for covering the missing issues of phase response on Filters second order in subsequent editions.
Based on the theory:
The 1st order high-pass filter has a phase response decreasing from 90 degrees (0 Hz) to 0 degrees (>100 KHz). The cutoff frequency has a phase of 45 deg
The 1st order PSF (bandpass) has a phase response that decreases from 90 degrees (0 Hz) to -90 degrees (>100 KHz), with the peak filter capacity occurring at 0 degrees.
The 2nd order low-pass filter has a phase response that decreases from 0 deg (0 Hz) to -180 deg (>100 KHz). The cutoff frequency has a phase of -90 deg.
Setting the task of forming a crossover comes down to coordinating the phase response characteristics of its elements.
The most optimal way to match the phase response of the elements in this case turned out to be the method of changing the polarity of the midrange head, while the phase difference of the heads turns out to be quite linear in the active range and is on the order of tens of degrees, which theoretically should eliminate possible interference phenomena.
In order to somehow present the above, I offer a sketch of the phase response, drawn based on the remembered theory of filters, some sections of the purchased book, and an analytical approximation of the missing part, which kept me awake for several nights))
And so visually the phase response of the elements is on the top graph with straight polarity of all heads, on the bottom graph when the polarity of the midrange head changes.
As can be seen from the provided figures, for further coordination it is necessary to optimize the cutoff frequencies.
After a series of experiments, studying the characteristics of the heads, the cutoff frequencies chose the following (averaged):
1. - 400 Hz
2. - 3500 Hz
The frequency response of the phase response and other characteristics of the existing heads were entered into the modeling program, and the values of the elements, coils, capacitors, and attenuators were calculated. Using the coil calculation program, the length of the wire for winding was determined based on the existing wire and frames.
The results of modeling in the program confirmed the correctness of the theoretical concept, and the expected forms were sufficiently reflected in the graphs:
| frequency response | FCHH |
4.Sound source
The sound source is a stereo receiver DENON DRA - 500 AE (75 W), purchased from Audiomania. Quite a good device with confident sound and good radio reception.
5. Achieved results, impressions, conclusions.
Overall the sound has become more detailed. The middle by replacing the midrange speaker and filling the cocoon that insulates it with sound-absorbing material. The previous lows have gone away from the muttering, here strengthening the body, pasting the inside with natural felt, and filling with sound-absorbing material played a big role. In the high-frequency region, the harsh accent disappeared due to recalculation and matching of the non-native speaker with the crossover. At a volume close to maximum with an average balance of highs and lows, detail is preserved and there are no overtones of distortion. When reworking the speakers, the original grills and speaker frames were intentionally preserved, emphasizing the style of those distant Soviet times.
The opinion about the sound quality of the system was confirmed by more than one guest who came to see me during the holidays; everyone’s impressions were positive. A classmate of mine was specially invited, he is now working with concert equipment - a music lover who bought himself a gold audio monitor, after listening to the converted Radio Engineering, said - “Not bad - especially for the background.”
As they say, there is no limit to perfection))) Over the holidays, the idea arose to reconsider the HF sector. Expand the midrange crossover a bit to allow Visaton to open up more, also change the HF to Viaton + branded capacitor coils......
I thank those who have read this article for their attention, I am ready to provide the necessary comments if questions arise.
Taking this opportunity, I would like to wish everyone a Happy New Year and Merry Christmas, and wish new achievements and achievements in the new year that would serve as a new qualitative step for the next year!
01/11/11 Pavel.
Manufacturer: Riga Radio Plant named after. A. S. Popova.
Purpose: speaker systems are designed for high-quality sound reproduction as part of household electronic equipment.
Specifications:
3-way floorstanding speaker with bass reflex
Frequency range: 25 – 25000 Hz
Frequency response unevenness in the range 100-8000 Hz: ±4 dB
Sensitivity in the range 100-8000 Hz: 89 dB
Resistance: 8 ohms
Minimum impedance value: 7.6 ohms
Rated power: 35W
Maximum (nameplate) power: 90 W
Short-term power: 600 W
Installed speakers:
Dimensions (HxWxD): 710x360x285 mm
Description:
The acoustic system is similar except for the midrange speaker; the S-100F is installed with MAXID magnetic fluid. The speakers have two smooth playback level controls for midrange and treble. Adjustment limits are from 0 to -6 dB in the ranges of 500-5000 Hz and 5000-20000 Hz. In the “-6 dB” position the signal is weakened by 2 times. The speakers have LED indication of speaker overloads.
The body is made in the form of a rectangular non-separable box made of chipboard, veneered with valuable wood veneer. The wall thickness is 16 mm, the front panel is plywood 22 mm thick. At the joints of the housing walls, elements are installed on the inside that increase the strength and rigidity of the housing.
The heads are each framed with decorative black plates with four mounting holes. The midrange head is isolated on the inside from the total volume of the housing by a special plastic casing in the shape of a truncated cone. The LF head is located on the front panel along a vertical axis, and the MF and HF heads are shifted relative to this axis to the left. In the upper corner of the front panel there are overload indicators, and in the lower part there is a rectangular bass reflex hole, measuring 108x35 mm and tuning frequency 25 Hz. The nameplate on the midrange and treble regulators shows the frequency response curve and the manufacturer's logo. In addition, the front panel has bushings for attaching a decorative frame with fabric. On the rear wall, in the lower part, a block with terminals and a nameplate are attached. The set includes grills with acoustically transparent fabric.
The internal volume of the speaker is 45 liters. To reduce the influence on the frequency response of sound pressure and the sound quality of the speaker resonances of the internal volume of the housing, it is filled with a sound absorber, which is mats of technical wool, covered with gauze.
Inside the case, on one board, there are electrical filters that ensure separation of the speaker bands. The frequency section between LF/MF is 750±50 Hz, between MF/HF - 5000±500 Hz. The design of the filters and the overload indication unit uses resistors such as BC, MLT, SP3-38B, S5-35I, PPB, capacitors such as MBGO-2, K50-12, K75-11 and inductors on plastic cast frames.
No matter what the snobs say, the Soviets were at the highest level. Even now they can bypass many modern beepers. And after appropriate modifications, even budget speaker systems from Yamaha cannot compare with them. And now we will look at the legendary Radiotehnika S90. This is a symbol Even abroad they noted the high quality of this (at one time). Therefore, it makes sense to consider these columns. Moreover, many people still use them to this day.
A little history
Radiotehnika S90 speakers were first released in the early eighties of the last century. They were produced by a plant located in Latvia, which became an additional incentive for citizens to buy them. Despite the rather high price, the speakers sold like hot cakes. People saved for a long time, did not eat enough, hiccupped them wherever possible. They even purchased used speaker systems. Just to decorate your closets with “Radio Engineering”.
Nowadays, many audiophiles are still chasing this speaker system. Speakers "Radio Engineering" are the dream of every connoisseur of high-quality sound. But now they can only be purchased on the secondary market. And it’s far from a fact that their condition will be acceptable (they do. However, this acoustic system can give a head start to many modern speakers. And after appropriate modifications, it completely turns into Hi-End class acoustics. And this is a completely different level.
Appearance and Design
Looks impressive from Radiotekhnika. These are very large speakers. Each of them weighs about 15-20 kilograms. This is not to mention the fact that carrying them is not very convenient due to the bulky and bulky case. The front panel (like the entire body) is covered with veneer. There are several color combinations. The speakers are covered with a metal mesh. Only the tweeter is not covered with protection. This is, of course, good, but it does not have the best effect on the acoustic properties of the speakers. However, the design is quite acceptable. Much better than other speakers of “clumsy” Soviet production.
On the right side of the mid-frequency and high-frequency speakers there are two operating mode switches. It is unknown why they were placed here. A normal amplifier itself is capable of switching modes. And the job of speakers is to reproduce sound correctly. Nevertheless, Radiotehnika S90 has such switches. But during the finalization process they can be removed, because they have a very negative effect on the overall sound quality. But for those who appreciate retro and antiques, such proposals will seem blasphemous.
Specifications
So let's get down to the hard numbers. Normal speaker power is 35 watts. But these beauties can easily give out 90. That is why they were called “the neighbors’ nightmare.” However, to fully exploit them, stereo amplifiers of appropriate power are required. Only then will this speaker system really sound. The frequency range starts at 20 hertz and ends at 25,000 hertz. This wide range allows the speakers to reproduce almost all instruments quite reliably. The frequency response is quite acceptable for an acoustic system of this level. You can't expect any miracles from her. But the sound is quite decent.
Now comes the fun part - the woofer. This is the legendary "Din 75 GD". The thing is, of course, good, but it does not produce perfectly reliable bass. If the low-frequency speaker is at least something, then the mid-frequency and low-frequency drivers, although they cope with their task, can not be called “kosher”. Ordinary paper bubbles. It would be much better to replace them with Kevlar or silk canopies during rework. That's when the big speakers will start sounding. And it’s better to rewind the woofer, since in used speakers it often burns out due to “super-mega bass”.
Sound quality
As mentioned above, Radiotekhnika speakers with standard components cannot boast of very clean and correct sound. But the quality is enough for not very demanding listeners. The acoustic system copes well with instrumental music (light rock, jazz, blues), and the electronic system also works well. But heavy and other subgenres of great and terrible metal - not so much. That is, the speakers reproduce it as expected, but the woofer jerks so much that it could easily break. Especially when listening to those groups that often abuse the cardan on the kick drum.
The classics also go well. This is probably the only genre that the Radiotehnika S90 copes with very well. All instruments sound crystal clear. Nothing gets ahead of itself. Even audiophiles may enjoy listening to classics on these speakers. However, it’s impossible to call this speaker system a Hi-End item. To achieve this level, the speakers will have to be modified. As standard, this is an average but confident Hi-Fi. But the Soviet people didn’t need more.
Amplifiers for S90
In order for passive acoustics to sound good, high-quality stereo amplifiers are also required. It should be noted that the “nineties” can only be driven and fully revealed by a very powerful amplifier. The Soviet vehicles "Brig" and "Odyssey" will cope with such work perfectly. These monsters are capable of getting everything out of the speakers. Amphiton U-001 will also do a good job. Just don’t even think about connecting this speaker system to the Vega 50U. The amplifier will immediately refuse to work even at minimum volume.
The ideal option for this speaker system is the Radiotekhnika amplifier. They were produced in huge quantities, with varying power and resistance. Therefore, finding such a thing on the secondary market is not a problem. There are more than enough amplifiers of this type that are suitable in terms of power. You can, of course, puzzle yourself and connect these speakers to a completely modern receiver like Yamaha. But then such a kit will go far beyond the “budget” scope. And such a decision is not worth the candle. It's like putting a Porsche engine into a Zaporozhets. It's possible, but there's no point.
Price S90
Now let's look at the most interesting quality of Radiotehnika S90. The price on the secondary market depends on the “kill” of the kit and its originality. Speakers in standard configuration and in decent condition will cost from 1000 to 2000 rubles. Depending on how good they look. Speakers with a whole internal system cost almost the same. You can even find ones that are barely used. It all depends on the seller himself and the buyer’s level of awareness. Speakers modified according to all the rules will cost more, since this is an acoustic system of a completely different class. They will cost about 3,000 rubles.
The Radiotekhnika amplifier will also cost about the same amount. Monsters like the Brig or Odyssey in perfect condition will cost around 15,000 rubles. But the problem is that finding them is almost impossible. In total, the approximate cost of the complete set will be approximately 6,000 rubles. Much better than an obscure Chinese speaker system for the same money. However, this is an approximate cost. It may vary depending on the degree of modification of the speaker system and its condition. But it still turns out to be much more profitable. And the sound quality will be at the same level.
Positive feedback from owners
Now let's look at the reviews about the Radiotehnika S90 speaker system. The amplifier is a separate topic, so we will not consider it here. So what will the owners say? Positive and negative reviews about these speakers go neck and neck. Competent audiophiles have long since finalized their “nineties” and therefore their reviews are laudatory panegyrics addressed to Soviet speakers. There is clear sound, clearly defined bass, wide range, versatility (for all genres) with some equalizer adjustment. Also an important advantage for many was the completely wooden body. And the power of these speakers is the talk of the town. Everyone noted this quality.
Negative reviews from owners
However, there are also snobs who are not satisfied with the sound quality of this speaker system. They note insufficient definition of mid and high frequencies (and this is true). After so many years of use, the case is simply rattling. The subwoofer thumps out of place. But, comrades, any thing needs to be monitored and timely prevention carried out. This also applies to speakers. After the appropriate procedures, they will sound completely different. Dissatisfied S90 owners - take note!
Conclusion
Radiotehnika S90 is one of the most preferred budget options. It copes with its responsibilities much better than any modern acoustics from China, is highly customizable and can provide Hi-End class sound. What else does a music lover need to be happy?
