DIY audio speaker speaker repair

In detail: do-it-yourself speaker speaker repair from a real master for the site my.housecope.com.

Acoustic systems are divided into active, passive, the difference is limited by the presence of sound processing chips inside, powered by electric current. Amplifiers, filters, interfaces for reading flash media, decoding compressed audio formats. In the latter case, the speaker system approximates the functionality of the player. Consider what to do when the speakers are not working. The speakers include a myriad of sound reproducing devices, readers are interested in how they repair speakers with their own hands. You will need special glue. In the days of the USSR, BF 4, AK 20. Solvents are selected accordingly (based on glue). It will be necessary, disassembling, dismantling the connection, and repairing the speaker system yourself.

A movable part with a rigid plate creates air vibrations that are perceived by the human ear.

Do-it-yourself repair of acoustic systems, doubting how the device works, is supposed to use the principle - do not harm. Regardless of the size, the speaker of the speaker system is formed by electrical, mechanical parts. The first is formed mainly by inductors. The second includes a permanent magnet, a membrane. Here is an incomplete classification of speakers of acoustic systems.

Readers are familiar with naturally occurring audio reproducing devices. There is not always a coil in the speaker system. Therefore, before the repair, in the process, the master performs the correct classification of the devices, properly carrying out the necessary operations.

Video (click to play).

Partially touched the device. Let's consider in more detail the electrodynamic models. The diffuser forms the support for the cap. It is represented by the semblance of a wide horn on which the coil is glued from the back side. Flexible copper conductors that carry an electric current, punching the diffuser from the inside, fit directly to the membrane cap. The soldering points are visible from the front of the speaker. The coil is light; it is required to provide a relatively low inertia of the system. Even the tuning fork A of the first octave lies at 440 Hz. It is clear that for fluctuations of the indicated speed, the moving part of the speaker of the acoustics must be light.

The magnet is fixed on the bed. Usually circular. An inductor runs in both directions in the hole, moving the cap-membrane assembly. The connecting wires make constant vibrations. A centering washer is used to position the movable part along the vertical, horizontal axis. Perforated piece of elastic material, centering the location of the cap, diffuser. The centering washer does not interfere with the displacement of the moving part along the axis of symmetry. The repair is ridiculously simple:

Since the membrane and cap do not break, it is a matter of checking the electrical installation, the soldering points of the wires, the integrity of the coil.

Inductance is wound in the image and likeness of the old one. Each layer of turns is coated with BF 4 glue. Poor soldering is performed anew. Select the appropriate inductance winding technique. Usually a special device is made, formed by two pairs of racks, standing opposite each other on a long board. Both are connected by axles. One contains the core of the new coil, the other contains the purchased wire. It is recommended to buy the wire with varnish insulation. It is necessary to maintain the correct thickness. You can measure using a vernier caliper.

Winding is relatively fast while the glue dries. The coils fit tightly to one another, adhering to the shuttle principle. It is important to maintain the correct number of turns, properly position the terminals.

It is often necessary to disassemble a speaker of a speaker system for repair. Stock up on solvent. The glued joints are wetted, waiting for a fixed time. Please note: the joints are carefully cleaned. It is made regardless of the glue used to assemble the speaker of the speaker system.

Speakers are different types of speaker systems, each with a limited frequency response. Everyone works as a kind of mechanical filter. However, it happens that you need to shift the range ... You can raise the resonance frequencies of the electrodynamic system by varnishing the centering washer. Used 5-10% solution of ZAPON, cellulose in acetone. The varnish is applied with a soft brush in a circle. Avoid misaligning the moving part of the loudspeaker. Consecutively performing the operations, we will increase the resonance frequency by 1.5–2 times, approximately one octave.

To lower the range, weights should be glued to the moving part. The correct ring of cardboard is attached to the back of the diffuser. It is necessary to more precisely maintain the symmetry of the arrangement of the parts. The sound pressure drops rapidly. The volume decreases, the range is narrowed from the high frequency side. However, in the area of resonance, the loudspeaker will perform well.

You can expand the range in both directions (if there is no cap). In the center, from the front, a truncated cone is glued above the inductance coil of the speaker of the speaker system. The mass is made as small as possible. Thin, thick paper impregnated with ZAPON varnish will do. The top plate is equal to the coil, the height is half the cone, the taper is 70 degrees. Due to the increase in the mass of the moving part, the resonant frequency decreases, but the upper edge of the range rises, thanks to the rigid core, which is harder than the diffuser. As a result, the spectrum of the reproduced sounds expands in both directions. The total increase will be one and a half or two octaves, the game is worth the candle. Take care to correctly configure the electronic part: if there are passive filters on capacitors and resistors, they will limit (cut off) the capabilities of the mechanics.

Craftsmen increase the sound pressure at the resonant frequency for an unshielded magnetic system. Try to find one or a similar set ring. Then glue the second magnet on the reverse side of the one standing, the interaction of the fields will increase, therefore, the strength of the sound will increase.

The speaker system is simple and can break, they said. We hope the renovation goes off without a hitch.

Hello. In the last article, I promised the blog subscribers that I would describe how to repair audio speakers with a breakdown in the form of an inoperative channel, and even with my own hands.

Today we will talk about this. If you read the article where I showed a way to solve the problem with the left speaker not working, you realized that it was not at all about the audio settings in the operating system. The whole problem was in the 3.5 plug that connects to the audio output of the computer sound card. Usually this output is green.

at the exit they give out 8 watts each and, in principle, enough for an apartment.

I somehow gave these speakers to a friend for a couple of days of use. Taking them back, I did not immediately check their condition. On New Year's Eve, I decided to connect and listen to how things were going, it turned out that it was bad. One channel did not work, and it was not at all about the settings. The photo below shows what the problem is:

The tip of the plug was broken off, and as you know, this is the contact for the left channel of the speakers.

If you are faced with the same problem, then read on and find out how to solve it.

In my case, everything is obvious. The broken tip is to blame. But what if the plug is intact, but there is still no sound in one speaker? Then use a tester and ring the contacts for integrity from the 3.5 pin itself to the speakers.

I started to replace. It is well disassembled and has an insulating tube.By promoting the purchase, as shown in the screenshot:

I decided to disassemble the old connector in order to solder the channels to the new one in similar places:

but, as you can see, it didn't work out. Everything is sealed to the conscience. So, throwing away the old one, a cord of 3 wires remains in your hands.

It remains to understand which channel, to which of them belongs. We disassemble the column in which all the main electronics are located. It is easy to find it, since all the wires and the cord from the 220 network come out of it. Disassembling labor is not enough to unscrew 4 screws from the back of the column.

After disassembling, we examine the board and find the place into which these very channels and mass are soldered.

In the photo below, it is clear that the red wire is the right channel. ® , white is left (L) and black is mass or ground (G).

Below I present to your attention the wiring of the channels of the new plug, which must be installed.

We strip the wires from the peel, long enough for installation. I do this procedure by touching the peel to the tip of the soldering iron and drawing it to the right place along the length.

After that, the sting should be cleaned of the mass caked on it from the melted wire wrapper. Here I am using the advice of my friend, with the help of whom a video was filmed for one of the articles. The soldering iron should be cleaned with an ordinary metal dish brush.

We solder the channels according to the picture I already showed:

To do everything neatly and to be sure that no short circuit occurs inside the new plug, I used a glue gun.

I took such a precautionary measure due to the fact that the new connector has not only just been replaced, but it is also made of metal.

After planting the channels in their places in the process of repairing audio speakers, heating the glue gun, we fill the contacts with glue so that they do not come into contact with each other.

At the final stage, we put insulation on top of our glued mass and screw the connector body itself onto it.

The whole work took me about 30 minutes, and I was very pleased with the result. After checking the work through my smartphone, I set about installing the speakers in their original place. This is how we figured out how to repair audio speakers with a failed left channel.

Thank you all for your attention. I recommend subscribing to the free blog newsletter and you will receive new articles in your mailbox.

Today, the number of good sound lovers who just throw out a wheezing speaker is not decreasing! At the same time, the cost of an analogue can be a tangible amount. I think the following will help anyone who has hands that grow out of the right place to fix the speaker.

Available - a miracle of design thought, once the former column S-30 (10AC-222), now serving as one of the autosubs. A week later, after the mutation, the patient began to show signs of the disease - he emitted extraneous overtones when working out the bass parts, wheezed a little. It was decided to conduct an autopsy.

After autopsy, a diseased organ was removed from the patient's body - woofer 25GDN-1-4, 86 of release. The organ clearly needed operation - when gently pressing the diffuser, an extraneous sound was heard (very similar to a quiet click), and when ringing in various tones (generated by the nchtoner program), a clearly audible rattling-crackling sound was heard with a large diffuser stroke and when ultra-low (5-15Hz) ) frequencies. It was decided to trepan this organ

First, the patient's flexible lead wires were sealed off (from the side of the contact pads)

Then a solvent (646 or any other capable of dissolving glue, such as "Moment") was moistened with a syringe with a needle, the place where the dust cap and the diffuser were glued (along the perimeter).

... the place where the centering washer is glued to the diffuser (around the perimeter).

... and the place where the diffuser itself is glued to the basket of the diffuser holder (again around the perimeter)

In this state, the speaker was left for 15 minutes with periodic repetition of the previous three points (as the solvent was absorbed / evaporated)

Attention! When working with a solvent, safety measures should be observed - avoid contact with skin (use rubber gloves!) And mucous membranes! Do not eat or smoke! Work in a well ventilated area!

When wetting - use a small amount of solvent, avoiding getting it on the gluing area of the coil and centering washer!

Depending on the type of solvent and air temperature, after 10-15 minutes of the above operations, using a sharp object, you can gently pry off the dust cap and remove it. The cap should either come off very easily or offer very little resistance. If you need to make significant effort, repeat the operations with wetting its edges with a solvent and waiting!

After peeling off the cap, carefully pour out the remaining solvent from the recess near the coil mandrel (by turning the patient over).

By this time, the centering washer has time to peel off. Carefully, without using any efforts, we separate it from the basket of the diffuser holder. if necessary, re-wet the gluing site with a solvent.

Wet the place where the diffuser is glued to the diffuser holder. We wait. We wet again and wait again. After about 10 minutes, you can try to peel off the diffuser. Ideally, it should detach from the diffuser holder (together with the coil and centering washer) without effort. But sometimes he needs a little help (the main thing is accuracy! Do not damage the rubber suspension.)

We clean the gluing points from the old glue and dry the disassembled speaker. We examine the disassembled patient for a malfunction. We look at the coil. If there are no scuffs and loose turns on it, we leave it alone. When peeling off the coil, glue it back with a thin layer of BF-2 glue.

We carefully inspect the place where the lead wires are attached to the diffuser. So it is - the patient has the most common malfunction in old speakers with a large diffuser travel. The lead wire at the attachment point is frayed / broken. What kind of contact can we talk about when everything hangs on a thread passed into the center of the wiring!

Gently bend back the copper "antennae".

... and unsolder the lead wires.

We repeat the operation for the second wiring (even if he is still alive - the disease is easier to prevent!)

We cut the supply wiring at the break point.

... and we serve the resulting ends (of course - first we use rosin). Here you need to be careful! Use a small amount of low-melting solder - the solder is absorbed into the wire like a sponge!

Gently solder the wiring into place, bend the copper "antennae" and glue (Moment, BF-2) the place where the wiring adheres to the diffuser. Remember - you cannot solder the wires to the fastening "antennae"! Otherwise, how can the wiring be changed again in ten years?

We collect the speaker. We put the diffuser with the entire “household” into the diffuser holder, orienting the wiring to the places of their attachment. Then we check the correctness of the polarity - when connecting a 1.5V AA battery to the terminals, when connecting the “+” battery to the “+” of the speaker, the diffuser will “jump out” of the basket. We put the diffuser so that its “+” lead wire is at the “+” mark on the speaker basket.

We solder the lead wires to the contact pads. Please note that the length of the wires has decreased by almost half a centimeter. Therefore, we solder them not as it was at the factory - to the hole in the plate, but with a minimum margin to maintain the length.

We center the diffuser in its basket using photographic film (or thick paper), which we place in the gap between the core and the coil. The main rule is to place the centering evenly around the perimeter, to maintain the same gap.The amount (or thickness) of the centering should be such that when the diffuser is slightly protruding outward, it freely rests on it and does not fall inward. For the 25GDN-1-4 speaker, 4 pieces of film are enough for this, placed in pairs in front of each other. The length of the film should be such that it would not interfere if you put the speaker on the diffuser. For what - read below. We glue the diffuser. We use the indication for the glue used (I recommend "Moment", the main selection criterion, so that the glue can be subsequently dissolved with a solvent). I usually stick out the diffuser 1-1.5 cm up so that the centering washer does not touch the basket of the diffuser holder, then I apply a thin layer of glue on it and the basket with a brush, wait and firmly push the diffuser inside, additionally press the washer against the basket around the perimeter with my fingers ... Then I glue the diffuser (in the retracted state, avoiding distortion).

We leave the speaker upside down for several hours under load (this is why our film should not protrude beyond the plane of the diffuser!).

Then we check the speaker for correct assembly. We take out the centering and carefully check the diffuser travel with our fingers. It should walk easily, without emitting overtones (there should be no touching of the coil and core!). We connect the speaker to the amplifier and send low-frequency tones of low volume to it. Extraneous sounds should be absent. In case of improper gluing (misalignment, etc.), the speaker must be glued (see above) and reassembled, being careful! With a high-quality assembly, we get 99% of a fully working speaker.

We glue the edge of the dust cap with glue, wait and carefully glue it to the diffuser. Here you need accuracy and precision - a crookedly glued cap does not affect the sound quality, but it spoils the speaker's appearance very much. when gluing, do not press on the center of the cap. It can bend from this and you will have to peel it off, straighten it, coat it from the inside with a thin layer of epoxy for strength and stick it back.

We wait until all parts are completely glued together (about a day) and put the finished speaker in its place. We enjoy the sound, which is no worse than that of the new factory analogous speaker.

That's it, now you can see that fixing a speaker is an easy task. The main thing is slowness and accuracy! So in an hour, you can slowly repair almost any woofer or midrange speaker of domestic or foreign production (for gluing imported speakers, a more powerful solvent is often required, such as acetone or toluene, carefully - they are poisonous.) Having a similar defect.

Yes, after the operation, the former patient got a second wind and the cheerful yellow subs continue to do their hard bass work:

Speaker systems can be active or passive. Internally, they have different microcircuits used to process audio.
In order for the sound to be of high quality, many devices are used to reproduce it. But all these devices cannot be seen with the naked eye, since they are located inside.
But everyone who owns them should know how the repair of loudspeakers takes place. Repair of acoustic buttons and other elements can be done with your own hands, if you know the speaker device.
In our case, we will consider the situation when the speaker speakers stopped working. You need to purchase special glue in advance, which may be needed during the repair process.
In general, any quick-drying glue you can find will do. It may just happen that during dismantling you will have to disassemble the glued joints. After that, they will need to be collected back somehow.

Before you start repairing your loudspeakers, you should know how the system works. This is necessary in order not to harm her in the process of performing certain actions.
Despite the size of the speaker, it has two components: mechanical and electrical. The first includes an induced current coil.
The second contains a magnet and a special membrane. At first glance, this mechanism seems to be simple, but it is not.
For this, you may need a speaker classification:

Reel to reel. Their principle of operation resembles the operation of a gas water heater (used to heat water). The ring of the magnet makes it move due to the formation of current in it.

Note: the device will work as long as all the turns of the coil are intact. Therefore, if the coil speaker does not work, then first of all you should pay attention to the integrity of the coil.

Tape. In this case, the variable magnet is a narrow corrugation.
At the same time, there is no coil inside, as in the previous version. To use such a device, you must purchase matching transformers in advance, which must be connected to the circuit.
Most often, these transformers are already installed from the factory.

Note: it is their presence or absence that allows you to quickly find out the type of speaker.

Isodynamic, which include a square or round spiral. It carries out circular movements together with the membrane, being under the influence of a magnetic field.

Electrostatic speakers. Their main difference is that they work without any movement. The current is initially already in the circuit, so you do not need to take any action for it to be formed.
In this case, the membrane moves a little, but it does not perform any translational movements.

Note: They are ideal for high-frequency speakers.

Capacitor, which includes two electrodes. One of them is quite massive, since it performs an important function - the supply of variable potential.
It acts as a support for the second electrode. By the way, instead of the second, you can use a foil twisted into a thin tube.
There are also other types of speakers, but only the most popular and common ones were considered.

The speakers work as follows:

Thin wires go to the cap located on the membrane. The cap itself is attached with a diffuser.
So these wires pierce it so that they have access directly to the cap.
The coil should be light, as it is necessary to achieve low inertia in the system. After all, the frequency of oscillations in the dynamics is enormous, therefore, in order to move at such a speed, the moving part of the speaker does not have to be heavy.
The magnet is stationary. Most often it is in the shape of a ring. A coil with an induced current is located in the hole.
As a rule, it moves back and forth. It also sets in motion a membrane with a cap.
The connecting wires are also in constant motion. So that the moving parts do not move from their place, they are connected in the center with a special washer, which helps to ensure that the axis of symmetry is not violated.

Speaker repair is a fairly straightforward process. The cap and membrane rarely break.
Most often, the coil fails. You should also check the soldering points of the wires, since it is possible that one of them has come off.

The old turns should be removed.

Wrap inductance on the coil as it was on the old one.

Each layer should be carefully greased with glue so that the turns are not moving.

Note: it is because of the high mobility that the turns can break. Therefore, you need to do everything possible to ensure that they are fixed in the best possible way.

The wire can be wound in any convenient way. The simplest option is to take two racks.
Place them parallel to each other and connect with an axis. Place the core on one side and the store wire on the other. The wiring should be wound quickly until the glue is dry.

Note: the wire must be lacquered.
First, it will improve its quality, so it will not rip as quickly. And secondly, it will be less likely that a short circuit will occur in the system.

The coils fall on top of each other. In this case, it is necessary to ensure that there is a sufficient number of revolutions.
In addition, you need to correctly place the conclusions.

Acoustic speaker in the car

Quite often, in the process of repairing loudspeakers, you have to disassemble the speakers. Therefore, you should stock up on solvent before starting repairs.
All glued joints must be moistened with glue and wait a while. Particular attention is paid to cleaning the joints.
Thus, you can do the repair of speakers with your own hands, without leaving your home. Initially, you need to purchase glue, the price of which is scanty.
Before starting the repair yourself, you also need to review the photos and videos with this topic, of which there are a lot on the Internet. Instructions on this will also come in handy.

Earlier I wrote about the manufacture of audio speakers on Fostex FE206En fullrange speakers with a bass reflex. For their size and cost, the Fostex FE206En's dual bass reflex speakers really sound great. But I want more ...

Impressed by the excellent sound quality from the small two-way bass reflex speakers, I decided to go further. I want to build a pair of large back-horn loudspeakers on top of the cabinet.

At the rear of the loudspeaker, a bass reflex system and a double bass reflex are used so that the sound radiates from the rear of the speaker, a transformer is used to boost the Bass.

The difference between the two speakers is that (BLH) speaker enclosures make the most efficient use of the speaker backwave. At the rear, the cabinet does a Bass boost using a backwave from the speaker that travels through the maze.

The rest of the audio spectrum (mid and high frequency ranges) is radiated directly from the front of the waveform emitted by the speaker.

Some time after the carpentry work, the first of the two AU enclosures was made. In the photo below, you can see the complexity of the design and manufacture of speaker enclosures. They used thirty-six pieces of 21mm plywood in each speaker box, stainless steel screws, glue pins and clamps were used to assemble the boxes. Front baffle and bottom - double plywood.

To "amplify" sound reproduction, you can reduce the internal volume of the speaker using sound-absorbing material. Sound absorbing materials should be used directly behind the loudspeaker to smooth out the frequency response.

The Fostex FE206En datasheet includes a frequency response section as shown in the figure above. You will notice that above 2 kHz you will start to get a "mid-frequency spectrum". The speakers often sound bright here. One way to try to compensate for this natural upward effect of the FE206En's speakers is by positioning the speakers off-axis (ie, speaker convergence). The required convergence angle will vary depending on the geometry of the listening room, the amplifier, and the personal preference of the listener. Start experimenting with the toe acoustics around 30 degrees and adjust from there to your liking. Experiment to find the best speaker placement. Correct speaker placement will be rewarded with excellent acoustics!

Audio speaker on Fostex speakers

The final stages of assembly include the electrical wiring of the speaker - filter - connector.

The circuit is simple: one choke and one resistor in parallel to each other and in series with the speaker.

The figure below shows typical column filter layouts.

You can use an online calculator to determine the choke and resistor parameters based on the width of the deflector column and speaker.

Audio speakers on Fostex speakers

At a low cost of the system, which many can afford to make, speakers have turned out with decent sound quality!

Mark Houston, DIY Organizer, Melbourne Audio Club (diyaudioprojects.com)

Today, the open plan kitchen layout, kitchen-dining room combination is becoming more and more popular. This is facilitated by a number of positive aspects: a spacious, bright room, open space makes it possible to be in both rooms, it is very pleasant to cook, especially when you are with your family or friends, you can watch your favorite movie with your family while cooking.

The circuit is connected to an available radio station or radio receiver with the appropriate reception range. The standard loudspeaker turns off or reduces the volume of the receiver to "zero". After receiving a tone - signal, an audible signaling device about violation of the protected area is turned on. More details ...

Many of us have our own private houses, summer cottages, garden houses or "hacienda". If the dacha is located near the city, some families generally move there for the whole summer, and if there is a warm heated house, they spend a lot of time in winter. Life in nature is beautiful, no doubt about it, but still I want a little of the benefits of civilization like a water supply system. Often there is no central city water supply at the dacha, and a well is used as a source of water. The depth of the well is usually much greater than the depth of soil freezing (for the Moscow region, up to 1.5 meters). More details ...

How good it is sometimes in the summer on the street in a cool gazebo to listen to your favorite tracks ... We got together like that in the summer with a friend sat listening to some drummer on his old S30 Radiotehnika. Surprisingly, the columns, in spite of their already advanced age, were always hollowed out very well. But after a couple of tracks at full power of this ULF, one of the speakers began to wheeze strangely ...

Thinking about what happened, I started looking for the reason in the ULF, disassembled the amplifier and measured all the voltages. Everything turned out to be normal. After that I decided to swap the channels and turned on the sound for the whole ... All the same column with the same effect. I had to repair, by the way, this is not the first speaker repair, I already had experience in repairing the Chinese speaker of the Sven speaker

After the autopsy, it turned out that the inside was GDN 25, which I had previously seen only in pictures on the Internet.

Here is a photo of the speaker of the GDN 25

Having twisted the speaker and examined it from all sides, no defects were found. But then I slightly pressed down the diffuser, I found that the diffuser was torn off from the centering washer, which can be clearly seen in the photo

Rub the diffuser against the core of the magnet and if this nuisance is not eliminated, then in addition to the grinding, which presses on the ear, the sleeve will fray and close the coil, which can lead to the destruction of the ULF. Fortunately, such repairs are carried out very quickly and will not take much effort.

To repair the speaker, we need:

Glue. I used regular rubber, liquid 88 glue

Acetone. I used regular nail polish thinner.

Syringe. For easy bonding of the diffuser

When everything is ready, you can start repairing

You need to remove the dust cap to get to the speaker coil. To do this, you need to slowly soak the edges of the cap with acetone to soak the glue. It is convenient to do this using the same syringe. The photo clearly shows what needs to be done! The photo shows how the solvent has not yet been absorbed.

After the cap is soaked, it literally takes about 5 minutes, we carefully try to pry it by the edges, only very carefully because the diffuser can be damaged. If the cap does not slip, add more acetone. It should slide easily.

Here is the cap removed

As you can see, the speaker is still damp. He needs to be allowed to dry, literally half an hour is enough for this, this is in the summer and just not in the sun. Drying should be done in the shade and in a well-ventilated place ..

When the speaker is dry, we need to center the speaker. To put it simply, it is necessary to align the sleeve so that it does not touch the core at full speed.This is done using regular film from a camera. If it is not there, you can use an old X-ray photograph, or at worst, as I did, take an ordinary thick thin notebook cover.

So you need to twist the film into a tube and insert it between the core and the sleeve

And press down tightly so that the diffuser is well pressed against the washer. Then we collect the syringe with glue, so the thinner the glue, the better

And now we carefully glue the washer with a good layer of glue. Be careful. Hold the needle, because under the pressure of the piston, it sometimes flies out and can get injured.

We stretch with glue as seen in the photo

After you have stretched it once, look carefully, perhaps there is not enough glue and you need to walk again .. Remember that the quality of your work depends on the quality of the sound and the absence of alterations.
This completes the repair. Once again, check if the washer is pressed tightly and leave the speaker to dry for a day until the glue completely hardens.

After a day, we carefully take out the centering film and try to connect the speaker for testing. Drive it well and test its strength. If everything is normal, glue the cap back in place and put the speaker in the speaker. This completes the repair

Here are a couple more photos of the speakers Radiotehnika S-30

The repair is over. A year has passed since this speaker has been working and it still pleases with its sound. Therefore, do not be afraid to repair the speakers and do it with high quality so that you do not have to repeat the repair. And just good luck to you
From SW. Admin check

In general, a whole bunch of material, both magazine and a large number of Internet articles, is devoted to finalizing the columns. However, almost all of them fall into two main groups:

We twist AC (X) and enjoy the result, especially in comparison with AC (Y).
A large article on soldering wires and stuffing the case with cotton, followed by reasoning how everything became cool.

Domestic columns stand somewhat apart, where each model is described separately and in great detail, and the level of alterations is sometimes such that it is no longer possible to consider it a tweak in the usual sense. And it’s not so easy to repeat. Here I wanted to summarize all the experience, including my own, on fine-tuning the sound of the speakers in general, without omitting the wires with cotton wool. Focusing mainly on a remake with a price of $ 200 to $ 1000. The cheaper ones are often simply hopeless, while the more expensive ones are much more difficult to bring (more precisely, to bring them so that it does not get worse). From this point of view, the range from 200 to 1000 is the most optimal for investing a small amount of money - 10-20% of the price of the speakers - in order to close some articles of manufacturers' savings and talk about a significant increase in sound reliability.

Before describing the changes made to the columns, I would like to warn followers against typical mistakes that lead to the loss of unnecessary money, time and energy.

Decide finally. To climb or not to climb into the factory product, everyone decides for himself. However, if you are an insecure person in life, then it is better not to make irreversible actions. When making a tweak (especially a complex one), keep in mind that the sound of the speakers will be very remotely similar to the original. At the same time, the changes will not only be for the better. Often, alterations lead to the fact that the dirt that you just did not pay attention to comes out. This can be both the dirt of the speakers themselves (for example, due to incorrectly calculated filters, the resonance of the high-frequency head will come out), or the shortcomings of your electronics. This is something to keep in mind, and if the overall sound of your system suits you, rejoice, you are a happy person.

Do not hurry. Do not make a working layout out of columns for working out rework. It may turn out that after four disassembly you rip off half of the screws holding the speakers. Ideally, the columns should be disassembled two times. The first one is for reconnaissance: design revision, redrawing of the crossover, searching for potential weak points. The second - for revision - at once and all - that was planned. Self-tapping screws must be handled with care.Especially if the column wall thickness is less than 16mm. If necessary, you can drop PVA glue into the hole - this way you can partially restore the torn off thread. In addition, the more often you open the cases, the more chances you have of damaging the speakers and the finish, which may not be confused.

Don't skimp. It is worth spending a little money and not changing one garbage for another, so that later you will be perplexed - what a mess this upgrade is. Good components cost good money, and there's no getting around it. You must put at least a class higher than what is already in the columns. This primarily concerns capacitors in filters. Extremism, however, is also inappropriate. The design should be balanced, cram into SVENs (for example) Suprem at the price of one more such SVEN: an idea for an amateur.

A complex upgrade requires serious qualifications and experience of the performer, especially in relation to crossovers, as well as some measurement technology. If you do not have sufficient amateur radio experience, do not go beyond the improvements described below. The result can be unpredictable. However, almost certainly, for the worse.

Mechanical modifications of the cases are classics of the genre. Described in great detail and is almost the same everywhere. Available for anyone with the right screwdriver and a little desire. Let's start, however, without departing from the origins. Figure 1 shows typical speakers - shelf, floor standing two-way, and three-way. It is very easy to distinguish a three-strip from a two-and-a-half strip from the inside. Three-way has a separate compartment for the midrange speaker. All variants (more precisely, not all, but 95 percent) of two-stripes have one total volume for several woofer-midrange speakers.

2. Floor standing two-way speaker

3. Two-way with multiple woofers

4. Three-way speaker
Reinforcement struts in red.

Accordingly, each hull design has its own approach, with common initial goals. First, remove one woofer and look inside. Determine the wall thickness with a ruler (or caliper):

10-12mm - you're out of luck - as a rule, this is China, with third-freshness MDF - the possibilities for fine-tuning the case are severely limited by the ability to spoil it forever;
12-16mm is also not a lot, but here you can already do something without fear that the box will fall apart from careless movement;
16-20mm is normal, everything described below applies to this particular option.
More than 20mm - hardening, as a rule, does not require. In general, this is determined by tapping the body.
The exception is thin wooden cases (not from sawdust!) - such, as a rule, are made with high intent, they should not be strengthened either.

Of course, the housing must be sealed. All joints are glued, all accessories - terminals, FI ports, speakers - are seated without gaps, the screws are tightened tightly, without disruptions. Any backlashes are not allowed anywhere. In principle, this is nonsense, but in our age of widespread oppression of the working class and the rule of cash, the most surprising deviations from this norm are possible.

Next, glue in the spacers. Glue - wood or epoxy, PVA after all. Spacers - a piece of plywood, wood, old skirting board - should not be too bulky - in total, no more than 250 cm3 for a shelf (typical) and 1000 cm3 for a floor stand. Otherwise, it can significantly reduce the internal volume and affect the bass reflex setting. It should also be remembered that the front panel can be either the weakest or the strongest wall. The second case occurs when the front panel has a thickness of more than 18 mm and a speaker with a cast basket is mounted on it by six (for example) screws - the resulting strength is initially very high. In the first case, the front panel must be rigidly connected with a spacer to the rear panel (for floor-standing speakers). For shelf units, this measure is not so relevant. A spacer between the side walls is always desirable, since being located in the middle of the wall increases its resistance to deformation by a factor of four. Typical examples of installing spacers are shown in Fig. 1

Refinement of seats.If the front panel has sufficient thickness, then it is necessary to make a chamfer with a file or a jigsaw along the inner radius of the hole for the LF / MF driver (Fig. 2). This measure significantly facilitates the breathing of the dynamics, has a positive effect on the quality of the medium frequencies. It is necessary to skip those places where the speaker is attached to the case with self-tapping screws, so as not to impair the quality of the fastener tightening.

Between the speaker and the case, you need to install a gasket made of thin rubber or sealant (silicone, for example) to damp the parasitic vibrations of the head basket. The speaker magnet should be wrapped with a thin layer of bitumen mastic or foam rubber. You should also process the back of the speaker magnet system (if there is a hole there, you do not need to close it!). All these measures are aimed at reducing early reflections in the middle frequencies, concealing softness, soulfulness, and freedom of music presentation. This is especially effective for three-way speakers with a separate midrange speaker.

1. Chamfer; 2. Cover for the magnetic system

The tweeter refinement looks different and not so straightforward. It is necessary to treat the seat with a sealant, try to avoid any irregularities around the tweeter. The speaker housing should smoothly (preferably without seams at all) go into the front wall. The front panel should ideally have a soft texture (piano lacquer is one of the worst options). An example to follow is the Sonus Faber leather trim. All this is necessary to equalize the frequency response of the tweeter and reduce the diffraction effects of the speaker cabinet. Due to difficult conditions, these improvements can be classified as optional - if there is a possibility and desire. So, the installation of a tweeter with a diameter of 100 mm with a protrusion of 3 mm leads to an increase in the unevenness of its frequency response by about 2 dB.

Damping. Nominally, the column may contain:

A piece of thin padding polyester - throw it away and forget.
A sheet of cellular foam rubber on the back wall - put it aside for now.
Something third - bitumen or a combination of foam rubber and padding polyester - you can not change anything or shift it more carefully, or add the amount.

The general approach for damping is as follows. We apply bituminous mastic to the walls. It can be leplet (self-adhesive tape, sold in hardware stores), automobile bitumen from a spray can (this one will stink for a long time), fusion roof, or something else to your taste. The main thing is a viscous bitumen-like base. Processing - on the side walls in one layer (1-2mm), on the back in 2 layers (2-4mm), on the top, bottom - in one layer. If the woofer / midrange speaker is in close proximity to the lower (upper) wall of the cabinet, then this wall must be processed in two layers. If the edge of the woofer / midrange speaker is more than 5cm from the wall, you do not need to do this. The plastic pipe of the phase inverter must also be processed in one layer (wrap from the outside). Bitumen insulation reduces the Q-factor of vibrations of the walls of the case (audible when tapping), reduces the reflections of sound waves at medium and moderately low frequencies.

Further, (when everything is dry) we put (you can glue) felt about 6-10mm thick on the entire back wall. If there is no felt, put the previously set aside foam rubber in its place. You do not need to put anything on the side walls. You can go to the bottom. Next, we buy a synthetic winterizer (available in fabric stores). The width of the leaf is approximately 2.5 times the width of the column, the length of the leaf is from 0.5 to 0.7 of the height of the column. Thickness - 1-2cm. Folds into a roller and fits closer to the back wall. The principle is simple - the further the sintepon is from the walls, the better it works. Sintepon (like cotton wool, but it is much less convenient to work with, and its properties are not better) smeared on the walls, is practically useless.

Moderation is important at this stage. If you shift the absorbers, the bass will become amorphous, lose clarity. It will be necessary to disassemble again and reduce the amount of padding polyester - foam rubber.

All of these measures are powerful enough to seriously improve the fidelity of mid and mid-bass reproduction.In order to achieve nirvana, skills in using a soldering iron are required, as well as a certain amount of money for the purchase of components and wires.

At the first opportunity, it is necessary to completely (and without errors!) Redraw the crossover filter circuit, or look for the acoustics crossover circuit on the Internet. Adjusting them to mind can take months, there will be only general recommendations for replacing components, the rest is the lot of radio amateurs. However, even this little gives more than all games with wires, and is comparable in effect to replacing an amplifier. So, we draw the crossover, write down the polarity of the connection of the heads. There should be no differences in the columns either in denominations or in the polarity of the heads. You should be on your guard if the filter is not installed on the LF / MF speaker. There may be several reasons for this, but the consequence is one - in this case it is not worth changing the HF capacitors. This is either useless, or will lead to the dominance of the treble over the middle (or exacerbate this phenomenon). In any case, it will be necessary to change the scheme, which is already beyond the scope of a tweak for everyone. A typical variant may be like this - Fig. 3

Fig. 3 Crossover Infinity Alpha 30

It is clear that the ratings are not written on the coils, but recognizing them is much easier than it seems. This requires an LSP-CAD or LS-LAB (for example) and a couple of simple probes. But more on that elsewhere. Replacing inductances is fraught with a number of pitfalls, and it is much easier to make a mistake there. The main thing is capacitors. Everything is written on them. All conductors with a capacity of less than 20 μF must be changed to the same rating, but of a different type or to a higher operating voltage. The replacement logic is as follows:

Electrolytic (barrels with leads on one side) - can be changed by any of the following.
Lavsan, they are also mylar (rectangular blue and red, yellow barrels with leads on both sides) - for polypropylene or paper (KZK White Line, K78-34, K78-19, Mundorf MCap, Jantzen Cross Cap).
Polypropylene (healthy barrels with thick leads on both sides) - for any foil barrels, for example KZK Orange Line, top-class such as Audyn True Copper, Clarity Cap CMR, Mundorf Mcap Supreme - or you don't need to change it - depends on your appetites.

Suitable types of capacitors for crossover filters: from domestic ones, you can try the K78 series for an operating voltage of more than 100V, K-42U9. You can immediately forget about K73-16, K73-17. From the K73 series, if installed, then with an operating voltage of at least 400V. From the bourgeois - Mundorf, Audyn Cap, Solen, Jantzen, Multicap, Visaton and much more, the main thing is that finances allow. The difference in class is noticeable; more expensive capacitors tend to produce better sound.

Replacing capacitors gives a lot of new details in the sound, a significant reduction in porridge, expands and streamlines the sound stage, both in width and depth. Makes the sound richer and more expensive. Sound comfort is improved. Unfortunately, there are some drawbacks. In addition to the chances (in general, small, it all depends on the case) crawling out of previously unheard shoals, the loss of drive is possible, or rather, what was previously understood as drive. Its source is precisely the specific distortion of electrolytic capacitors. You should not be afraid of this, you hardly want to go back, but you need to be ready. As well as the fact that fresh capacitors must run in within 2-10 hours. Desirable on a decent amplifier power and spectrally rich material (rock, large orchestras).

Video (click to play).

And finally, the last number, the replacement of the internal wiring. Take a wire of obviously better quality than what is in the speaker. Replace all detachable connections with soldering. It is not worth making the wires too short - the column should be assembled and disassembled without inconvenience. The polarity of the connection must be strictly observed. Errors are not allowed here! Solder - silver-coated (if it is not there - nothing terrible will happen - honestly!). The wires themselves can be of any reputable company, price and design.