What to make a speaker coil from. Repairing a subwoofer at home

How to repair a speaker yourself? FAQ Part 1

This is the first part of the loudspeaker repair manual.

Here you will find information about the terminology used, speaker problems and the simple repair when only replacement of flexible leads is required. Other issues will be discussed in future articles.

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How does the dynamic head work?

The schematic drawing shows a cross-section of the speaker. This is roughly how low-frequency and mid-frequency loudspeaker heads are designed.

Suspension (corrugated).
Flexible output (pigtail).
Bracket (secures the braid to the diffuser).
Damper (protects the pigtail from breaking near the terminal).
Hole in the housing for flexible output.
Insulating strip (holds the terminal).
Terminal.
Solders connecting the flexible lead to the terminal and the coil lead.
Coil output.
Coil.
Speaker housing (basket, frame).
Diffuser (membrane, diaphragm).
Dust cap (plug).
Centering washer.
Sleeve.
Pole piece.
Kern.
Top flange.
Magnet.
Bottom flange.

The letters N and S indicate Northern and South poles magnet This is the usual arrangement of the poles, although the opposite occurs occasionally.

In the next picture conventional drawing HF dynamics sectional view.

Coil output.
Insulating gasket.
Suspension (elastic extension of the dome).
Diffuser of dome design (membrane, diaphragm).

The main difference between tweeters and midrange and bass drivers is the absence of a centering washer.

In addition, many HF heads use a dome-shaped diffuser, often called a membrane. The dome and surround of such speakers are a single unit, and the sleeve is attached to the dome.

Since the stroke of the tweeter cone is small, the coil leads often play the role of flexible leads.

What are the types of speaker malfunctions?

Speaker malfunctions occur due to improper use, improper assembly, or normal wear and tear.

Incorrect operation.

Most often, damage occurs due to excess power supplied to the speaker. One of the reasons for such errors may be confusion with the method for determining the power of the speaker and amplifier. This is due to the fact that the same numerical values of effective, root-mean-square (RMS), or as it is also called, sinusoidal power and amplitude or musical power create a current in the speaker coil that differs by a factor of two.

Another reason that causes speaker overload is the careless redistribution of power between the heads of multi-way speakers. Most often, tweeters - tweeters - suffer from this. The fact is that the power of tweeters in multi-band systems can be less than 10% of the total speaker power. And if the user, using an equalizer, supplies most of the amplifier's power to the tweeter, then the death of the latter can be instantaneous.

There are also mechanical damage dust cap, suspension and diffuser. Sometimes these damages lead to misalignment, which in turn leads to the destruction of the coil and sleeve.

Destruction of the sleeve and coil can also be caused by displacement of the core. In such cases, the sleeve along with the coil gets jammed in the magnetic gap. This usually occurs as a result of a loudspeaker or speaker being dropped.

Unskilled assembly.

Due to unskilled assembly, the sleeve, coil, suspension or centering washer may come off. Poor quality gluing can also cause extraneous sounds.

Incorrect fastening flexible leads can significantly reduce their service life.

Normal wear and tear.

If the loudspeaker head is assembled well, the suspension and flexible leads suffer the most as a result of normal wear and tear. The diffuser can also collapse if its safety factor does not match the power of the speaker.

How to identify a faulty speaker element without disassembling?

All speaker malfunctions can be divided into “mechanical” and “electrical”. However, some electrical defects are very difficult to distinguish from mechanical defects by ear.

If no external changes, such as destruction of the corrugation or diffuser, are detected, but extraneous sounds appear in the form of crackling or periodic loss of sound occurs, then you should first check the flexible leads.

To do this, connect a dial ohmmeter to the speaker terminals and move the pigtails while the diffuser is stationary. If the ohmmeter needle moves, it means the flexible lead is damaged.

Other electrical defects include coil breakage and short-circuiting of part of the coil turns or the entire coil. These defects can also be detected using an ohmmeter.


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To do this, a master oscillator signal is supplied to the amplifier input.

A partially peeled off coil or part of the turns can be identified by smoothly changing the frequency of the generator or turning on the generator in the GKCh (Swinging Frequency Generator) mode.

When testing this speaker, the frequency range 20Hz...2kHz with a period of 3 seconds was used. In this speaker, apparently, a significant part of the coil has come unstuck, as overtones are heard over a wide frequency range. If a small fragment of the coil peels off from the sleeve, overtones can appear only at a certain frequency, and only when the damaged structural element enters resonance.

In some cases, to identify a malfunction, it is useful to use an infra-low frequency generator. This can help identify, for example, defects in the gluing of the rubber corrugation to the diffuser. The arrow shows the place where the oversound is formed.


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Rubbing the sleeve against the core or the coil against the inner surface of the upper flange can also be detected at a frequency of several hertz if you lightly press the corrugation waves with your fingers.

More serious damage to the speakers is even easier to detect.

So, for example, if something is heard when turning the speaker over, it means that part of the turns or the entire coil has fallen off the sleeve.

If the diffuser moves very poorly, then most likely the coil has fallen off and jammed the sleeve in the magnetic gap.

If the diffuser does not move at all, then the core may have moved and jammed the coil along with the sleeve.

Never attempt to disassemble such a speaker without first removing the sleeve, as this may also damage the cone.

How to replace speaker flex leads?

Use extreme caution when replacing flexible leads on an unassembled speaker, as a steel tool attracted by the magnetic system may damage the cone and dust cap.

If access to the flexible terminals (pigtails) of the speaker is free, then you can try to replace them without disassembling the speaker. But, in some cases, the speaker will still have to be disassembled. The picture shows a broken flexible lead.

Old flexible leads should be removed with the utmost care so as not to damage the diffuser or break the coil leads.

First, unbend the brass bracket that holds the flexible terminal, if there is one, of course.

Then the soldering area is heated with a soldering iron to separate both the flexible lead and the coil lead from the diffuser. Usually, after warming up, the glue softens and the leads can be removed.

How can I replace damaged flexible leads?

Of course, the simplest solution is to borrow flexible leads from another speaker of similar power or order from suppliers that sell spare parts for speakers. But, if this is not possible, or you want to save on spare parts, then you can make surrogate braids yourself.

The first and simpler option is to replace the failed pigtail with a piece of MGTF wire of a suitable cross-section. I don’t know who first came up with this, but it was with these flexible terminals that the once popular 4A32 speakers went on sale.

Another option is to make braids from a Soviet-made flexible telephone cable. It can still be found among all the junk at flea markets.

I am familiar with two types of such cable. In one, each wire consists of seven cores, and in the other of fourteen. Each core is made by winding copper tape onto a Mylar thread. In cross-section, the tape has the shape of a rectangle with dimensions of 0.03 x 0.3 mm.

0,03 * 0,3 * 14 = 0,126 (mm²)

As you can see, the cross-section is small, so for powerful speakers you can twist two or more stranded wires.

First, a section or sections of telephone cable are prepared using a soldering iron.

Insulation is removed in small areas, to avoid damage to the cores.

Then the cores of each stranded wire are untwisted and twisted again into one wire.

And finally, the flexible lead is carefully glued twice with rubber or 88 glue with an interval of 20 minutes.

Before the first gluing, the twist must be free so that the glue penetrates between the cores. Immediately after the first gluing, the strands are twisted to the end. The second gluing finally fixes the cores relative to each other.

Thus, it is possible to make a flexible lead for a speaker of any power.

If there is no telephone or MGTF wire, then as a temporary measure you can use MGShV wire or even a braid from a shielded wire, but such pigtails do not last long, and they put a greater load on the diffuser due to less flexibility.

When installing a flexible output, you need to take into account that the most weak points of this unit are the places where the pigtail is attached to the diffuser and the terminal.

If the fastening brackets are damaged or lost, the braid is secured with two crossed stitches of thread. Then the attachment point is glued with glue with a large dry residue. Weathered BF-2/BF-4 will do.

To prevent premature fracture of the pigtail, the attachment points are covered with several layers of rubber or 88 glue with a transition to a flexible terminal.

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

Available - a miracle of design thought, which was once a column S-30 (10AC-222), now performing the functions of one of the autosubs. A week after the mutation, the patient began to show signs of the disease - he made extraneous sounds when practicing bass lines, and wheezed slightly. A decision was made to perform an autopsy.

After the autopsy, the diseased organ was removed from the patient's body - a woofer 25GDN-1-4 produced in 1986. The organ clearly needed surgery - when you gently pressed the diffuser, an extraneous sound was heard (very similar to a quiet click), and when ringing with different tones (produced by the nchtoner program), a clearly audible scratching-crackling sound was heard with a large stroke of the diffuser and when applying ultra-low (5-15 Hz) ) frequencies. It was decided to trepanate this organ

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

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

Place where the centering washer is glued to the diffuser (along the perimeter)...

And the place where the diffuser itself is glued to the diffuser holder basket (again around the perimeter)

The speaker was left in this state for about 15 minutes with periodic repetition of the previous three steps (as the solvent was absorbed/evaporated)

Attention! When working with solvent, safety precautions should be observed - avoid contact with skin (work in rubber gloves!) and mucous membranes! Don't eat or smoke! Work in a well-ventilated area!

When wetting, use a small amount of solvent, avoiding getting it on the place where the coil and centering washer are glued!

Depending on the type of solvent and air temperature, after 10-15 minutes of the above operations, using a sharp object, you can carefully pry up the dust cap and remove it. The cap should either come off very easily or offer very little resistance. If you need to apply significant force, repeat the operation by wetting its edges with 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 come off. Carefully, without any effort, separate it from the diffuser holder basket. if necessary, re-wet the gluing area with solvent.

We wet the place where the diffuser is glued to the diffuser holder. We wait... We wet it again and wait again... After 10 minutes you can try to peel off the diffuser. Ideally, it should effortlessly separate from the diffuser holder (along with the coil and centering washer). But sometimes he needs a little help (the main thing is to be careful! Do not damage the rubber suspension!!!)

We clean the gluing areas from old glue and dry the disassembled speaker. We examine the disassembled patient to determine if there is a malfunction. Let's look at the reel. If there are no abrasions or loose threads on it, we leave it alone. When a thread comes off, glue it back on. thin layer glue BF-2.

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

Carefully bend the copper “tendrils”...

And unsolder the supply wire.

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

We cut off the supply wires at the break point...

And we tin the resulting ends (of course, we first use rosin). Care is required here! Use a small amount of low-melting solder - the solder is absorbed into the wiring like a sponge!

Carefully solder the wiring into place, bend the copper “tendrils” and glue it with glue (Moment, BF-2) where the wiring connects to the diffuser. Let us remember - you cannot solder wires to the fastening “antennae”! Otherwise, how can the wiring be changed again in ten years?

Assembling the speaker. We place the diffuser with all the “equipment” in the diffuser holder, orienting the wiring to the places where they are attached. Then we check the correct polarity - when connecting a 1.5V AA battery to the terminals, when connecting the “+” battery to the “+” speaker, the diffuser will “jump” out of the basket. We place the diffuser so that its “+” supply 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 centering should be such that when the diffuser is slightly protruded outward, it will freely rest on it and not fall inward. For the 25GDN-1-4 speaker, 4 pieces of photographic film, placed in pairs in front of each other, are enough for this. The length of the photographic film should be such that it does not interfere if you place the speaker on the diffuser. For what - read below. Glue the diffuser. We use the indication for the glue used (I recommend “Moment”, main criterion choice so that the glue can later be dissolved with a solvent). I usually stick the diffuser 1-1.5 cm up so that the centering washer does not touch the diffuser holder basket, then I apply a thin layer of glue to it and the basket with a brush, wait and firmly push the diffuser inside, additionally pressing the washer to the basket around the perimeter using my fingers . Then I glue the diffuser (in the retracted state, avoiding distortion).

We leave the speaker upside down for several hours under a load (this is why our photographic 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 movement of the diffuser with our fingers. It should walk easily, without making overtones (there should be no touching of the coil and the core!). We connect the speaker to the amplifier and feed it low-frequency tones at a low volume. There should be no extraneous sounds. If the gluing is incorrect (misalignment, etc.), the speaker must be unstuck (see above) and reassembled, being careful! With high-quality assembly, 99% of the time we will get a fully working speaker.

We coat the edge of the dust cap with glue, wait and carefully glue it to the diffuser. Care and precision are required here - a crookedly glued cap does not affect the sound quality, but it greatly spoils appearance dynamics. When gluing, do not press on the center of the cap!!! This may cause it to bend and you will have to peel it off, straighten it, coat the inside with a thin layer of epoxy for strength and glue it back.

We wait until all the 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 a new factory similar speaker.

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

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

You can often come across requests for help in repairing and rewinding the coils of burnt-out speakers; articles on this topic have been on the Internet for a long time, but we decided to make our own. So, I got my hands on a burnt-out Pioneer subwoofer speaker from a TS-WX303 subwoofer; the rated power of the speaker is about 250 Watts. It seems to me that the former owner went too far with the power and as a result our speaker burned out.

When you press the diffuser, a clearly audible grinding sound is produced, this is the coil rubbing against the magnetic core, possibly falling apart, after disassembling the speaker everything will become clear. The main difficulty is to disassemble the speaker, because it is very important not to damage the speaker suspension, it’s good when the suspensions are rubber, such ones come off and come off with a bang, in the case of foam rubber and their analogues, everything is not as simple as it might seem at first glance.

So, a photo of my patient:

Personally, I disassemble speakers in one of two ways: with a thin blade, or by soaking them in a solvent. In the second case, you need to work strictly outside or in a well-ventilated area, but not at home or in the entrance. You need to prepare in advance all the tools necessary for repairs, perhaps primary tools for dismantling the suspension and centering washer. The centering washer is located under the diffuser, usually yellow color made of thick pressed mesh fabric.

For soaking, you can use a syringe, draw the solvent into the syringe and carefully spray the outer parts of the suspension, in the place where it is glued to the “basket”. Soaking usually takes a long time; in 5 minutes you will not separate the suspension from the speaker body. The centering washer is soaked in exactly the same way.

This is not the first time I have rewinded speakers, and the dismantling operation for this speaker took me about 5-7 minutes. After soaking, we unsolder the conductive wires from the terminals and remove the diffuser with the coil from the frame. In principle, it is possible and necessary to unsolder the wires before soaking, it will be more convenient... We look at the photo of the coil of my burnt speaker:

The photo clearly shows overheated and charred turns of copper wire; this coil will have to be unwinded completely and rewound again. some unscrupulous repairmen practice next view repair: unwind part of the burnt wire and connect the break points together by soldering. Naturally, such a “homeless repair” will not last long; in addition, after unwinding some of the turns from the coil, it will noticeably reduce the total resistance of the speaker, which will certainly affect the power.

In general, if the coil is more or less alive, you can leave it, after soaking the coil with varnish, it will last - but not for long. This option is applicable for beginners, for those who are afraid to rewind the coil due to certain circumstances (for example, there is no necessary wire for rewinding).

Ideally, the speaker coil should be wound with BF-2 glue. It's not easy to find, but it's the most the best option. We glue the suspension with rubber glue 88, it is usually sold in small jars in construction stores, this glue is used to glue carpets onto subwoofers:

Finding the right wire is also a problem, good wire donors are contactor (starter) coils, which are sold separately in electrical equipment stores and are not expensive, this is exactly the wire I use. Also the right wire can be found in the degaussing loop of picture tubes (CRT), a sample of my wire for winding is below in the photo:

I removed this wire and rewound it just from the starter, the diameter of the wire is approximately 0.35, by the way, it is not recommended to wind it with a wire that is too thin because The speaker power will drop sharply. If you take a wire thinner than it was, then you will have to make a little more turns than there were, otherwise the resistance of the speaker will be less.

You need to wind the wire turn by turn, winding a speaker is a delicate and labor-intensive task, the main thing is not to abandon everything halfway... I wound it with a wire of approximately the same cross-section, I got 4 layers in total, covered each layer with BF-2 glue and let it dry for about two hours. Determining the required length of a new wire with sufficient accuracy is not so difficult; you need to calculate the length of one turn (knowing its radius), multiply by the number of turns in the layer and the number of layers. My speaker required about 20 meters of enamel wire. The diameter of the wire is determined using a micrometer or caliper. For winding, it is better to use a specialized machine, which greatly simplifies the entire winding process; if you don’t have such a machine, you will have to wind the coil manually.

After the glue has dried, we begin to assemble the speaker. I note that gluing the centering washer and the suspension at the same time is highly not recommended, because with a 99% probability, after the glue dries, your speaker will groan. First you need to glue either the centering washer or the suspension (I glue the first). That is, we coat the edges of the washer and the gluing points on the speaker body with a brush, let it dry a little and carefully put the diffuser on the body so that the coil does not rub against the magnetic core.

It will be difficult the first time, so you can coat the washer with glue not entirely, but only at several points; if centering is successful, you can re-glue it.Next, we glue the suspension; when connecting the suspension to the speaker basket, you need to center the suspension itself in parallel, so that there are no rustling or grinding noises when the diffuser moves. Afterwards we solder the conductive ones copper wires(conductors) running from the coil to the speaker terminals and let the speaker dry for 24 hours.

There is another, more accurate option for centering the coil, but to do this you will have to remove the cap from the diffuser. After removing the cap, we put the diffuser and coil in the basket, then take A4 paper, cut it along the wide side lengthwise into two halves and roll it into a tube of approximately the same diameter as the core of our speaker and carefully insert it into the gap between the core and the coil, then You can safely glue the centering washer with the suspension. After the glue has dried, pull out the paper and glue the cap back on.

Most dynamic heads are not intended for disassembly and are, as it were, disposable (non-separable, difficult to repair) components of speaker systems. In practice, it is successful to disassemble the speaker standard design and it is often possible to reassemble it. The main task is to soften the glue that holds many components dynamics, and separating them from each other without injury or deformation.

If you have questions about rewinding speakers, ask them here, we will try to help!

DIY woofer repair

Today, the number of lovers of good sound who simply throw away a wheezing speaker is not decreasing! At the same time, the cost of an analogue can amount to a significant amount.
I think that the following will help anyone who has a great desire and perseverance to repair the speaker rather than buy a new woofer.

Available - a miracle of design thought, which was once the S-30 column (10AC-222).

The organ clearly needed surgery - when you gently pressed the diffuser, an extraneous sound was heard (very similar to a quiet click). It was decided to trephine this organ.

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

Place where the centering washer is glued to the diffuser (along the perimeter)...

And the place where the diffuser itself is glued to the diffuser holder basket (again along the perimeter).

The speaker was left in this state for about 15 minutes with periodic repetition of the previous three steps (as the solvent was absorbed/evaporated)

Attention! When working with solvent, you should observe safety precautions - avoid contact with skin (work with rubber gloves!) and mucous membranes! Don't eat or smoke! Work in a well-ventilated area!

When wetting, use a small amount of solvent, avoiding getting it on the place where the coil and centering washer are glued!

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 come off. Carefully, without any effort, separate it from the diffuser holder basket. if necessary, re-wet the gluing area with solvent.

We clean the gluing areas from old glue and dry the disassembled speaker.

We examine the disassembled patient to determine if there is a malfunction. Let's look at the reel. If there are no abrasions or loose threads on it, we leave it alone. When a thread comes off, glue it back with a thin layer of BF-2 glue.

Carefully bend the copper “antennae”.

And unsolder the supply wire.
We repeat the operation for the second transaction (even if he is still alive - the disease is easier to prevent!)

We cut off the supply wires at the break point.

And we tin the resulting ends (of course, we first use rosin). Care is required here! Use a small amount of low-melting solder - the solder is absorbed into the wiring like a sponge!

Glue the diffuser. We use the indication for the glue used (I recommend “Moment”, the main selection criterion, so that the glue can later be dissolved with a solvent). I usually stick the diffuser 1-1.5 cm up so that the centering washer does not touch the diffuser holder basket, then I apply a thin layer of glue to it and the basket with a brush, wait and firmly push the diffuser inside, additionally pressing the washer to the basket around the perimeter using my fingers . Then I glue the diffuser (in the retracted state, avoiding distortion).

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

We coat the edge of the dust cap with glue, wait and carefully glue it to the diffuser. Care and precision are required here - a crookedly glued cap does not affect the sound quality, but it greatly spoils the appearance of the speaker. When gluing, do not press on the center of the cap!!! This may cause it to bend and you will have to peel it off, straighten it, coat the inside with a thin layer of epoxy for strength and glue it back.

We wait until all the 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 a new factory similar speaker.

After the operation, the speaker seemed to get a second wind, and he continued to stand and play in the subwoofer.

I like the old big, heavy speakers that were popular in the 90s. Despite their advanced age, they still sound pretty good and produce good bass. Recently I came across a pair of these speakers in a deplorable condition, but I decided to restore them and bring them back to life.

Professional repair of such speakers is very expensive, so it’s quite work equipment often they simply throw it away and buy modern subwoofers that are compact in size.

Will need

For proper repair Rubber or any other elastic gaskets of suitable diameter will be required. To accurately calculate right size gaskets, you need to measure the outer diameter of the cardboard cone and inner diameter steel frame, and based on this, look for gaskets of the required diameter.

Restoration work

I recorded the entire speaker repair process with a camera. Below is a detailed photo report of all steps.
The first step after removing the front panel is to remove the old seal and glue from the speaker circumference. To do this, I used a flat, sharp blade, but this must be done carefully so as not to damage the cardboard cone.

To center the cone while gluing it, you need access to the steel core. In large speakers, it is covered with a cardboard plug (it is glued), which must be carefully removed without damaging the cone. With cardboard plugs I managed to pry them off sharp knife, after which they came off along the adhesive connection, since they were not glued very tightly.

In small speakers, the dust caps turned out to be tightly glued, so they had to be carefully cut in a circle.

The next step is to accurately center the cone relative to the steel core. The free space between the cone and the core turned out to be different in each of the speakers. As an insulator and a kind of winding, I used strips of ordinary paper, which I pushed into the gap around the core until I achieved the most dense filling.

One of the small speakers required only one and a half turns of paper around the core, resulting in a slight displacement of the cone. Fortunately, in my case this circumstance did not affect the performance of the speaker, but I think that it would have been necessary to take thinner paper to complete two full turns.
For gluing rubber or foam seals, any household glue is suitable, for example, PVA or any similar one, which becomes transparent after drying. Glue is applied to the cone and speaker body along the edge of the hole, after which the gasket is carefully applied. You need to smooth it to the surface for a tighter fit and remove excess glue so as not to disturb the centering.

Once the glue has completely dried, you can remove the paper cup wrapped around the core. To check that the cone is properly balanced, lightly press it with your hand: it should vibrate freely without touching the steel core. If friction is present, all centering work should be redone and a new seal should be glued.

Now you need to install new damper pads around the speakers so that the front panel does not press or contact them. By the way, you can use old gaskets, completely free of glue, if they are in normal (not deformed) condition. The damper pad is glued to any glue. If the inner diameter of the new gasket is slightly smaller and covers rubber compressor(this may create interference), then it needs to be trimmed a little along the inner circumference so that the cone vibrates freely.

To glue the dust caps in place, I did the following:

I glued a narrow and folded strip of tape to each cap. The result is a convenient loop so that you can move the semicircular part.
I smeared the edges of the cap with glue.
Carefully placed the cap in its place and applied a little pressure until the glue set.