Audiomania DIY bookshelf speakers. Do-it-yourself bookshelf acoustics

Dedicated to those who have free time

We open a popular magazine about good sound and look with pleasure at the elegant images (if not the image) of acoustic systems, and there is something to look at. Powerful towers bristle with speakers in all directions, shine with their varnished sides, crush the parquet with sharp spikes and generally evoke a feeling of deep respect. The only downside they seem to have is, of course, the price. A completely logical question arises: what if you make a copy of a monster yourself? Buying a speaker is not difficult, assembling the housing, even if it is not so beautiful, also, the coils and capacitors can be domestic, carefully soldering 3 parts is a task for a 10th grade school student.

Considering the number of ready-made modules that Ebay offers, making a good amplifier is not much more difficult. What’s not there: switching, speaker protection, A-AB-D class boards, volume controls for every taste, beautiful cases made specifically for audio, handles, legs and transformers - just know, connect. In the next article we will definitely tell you how to assemble your own amplifier, which will not be inferior to most “branded” samples costing up to 60-70 thousand rubles.

You may come across unfamiliar words later in the text. Fortunately, an unknown audiophile came to our aid and left link to your personal archive of information on acoustics and amplifiers, there really is ALL and even more, we strongly recommend that you read it.

What to make it from? Plywood, MDF, chipboard, plastic, solid wood.

The world has seen many strange acoustic structures, for example, from concrete or cinder block. Still, the above-mentioned wood-based lumber remains the most “in demand”. Let's try to understand which one is “more correct”. The basic rule is - regardless of the material chosen, do not skimp on its quality, that is, price.

First comes the king of modern Hi-Fi and Hi-End industry - MDF, The vast majority of speakers, both expensive and cheap, are made from it. The reason is simple - low cost, ease of processing and finishing, including options with ready-made veneer, and the absence of bright resonances. With proper design, optimal results are guaranteed. We recommend it for use, nothing more to say.

Plastic- the concept is very loose, its “authority” is significantly undermined by cheap Chinese counterfeits, although it has no fewer advantages than any other material. We are passing by the problem of the inaccessible opportunity for an amateur to cast his own blanks from the desired material.

A good material for making an acoustic system enclosure can be Chipboard. Perhaps its main drawback is the many problems with finishing, no matter what you decide: paint, veneer or upholstery. Chipboard has a huge advantage: if you need to do it quickly and very cheaply, you can use a factory-made laminated chipboard (LDSP). In this case, it is unlikely that it will be possible to achieve high aesthetics, but the price and speed will leave all other contenders far behind. If we compare the resonant properties of materials in terms of suitability for speakers, chipboard takes first place, although the difference compared to MDF is small.

Capricious, but invariably desired by “seasoned audiophiles” madam plywood. There are several types of plywood - birch, coniferous, alder, laminated. Why capricious? Any plywood “leads”, that is, when the sheet dries, it changes its geometry, and chips often appear when sawing. It is also not the easiest material to finish if you want to get a “dull” matte color without visible edges, texture, or edges. The reason for enduring this torment is quite controversial: according to “experienced” people, only plywood gives that very living breath that chipboard and MDF “kill”. What I most incomprehensible is the desire to make a body out of “living” plywood and “kill” it with layers of putty, primer, paint, varnish in an attempt to hide the “terrible” joints with veins (layers of plywood), which look at their owner with silent reproach day and night . Options for special impregnation, at least with the same “Danish oil”, are much preferable; these dark “stripes” on the edges of the body are not so scary...

What kind of poverty is this chipboard-MDF? Maybe straight from solid oak, but thicker!? Don't rush to insert the speaker into the first hollow you see. Contrary to expectations array valuable wood does not enrich the sound in proportion to the money invested; moreover, it even requires additional damping compared to cheaper materials. Although its undoubted advantages are the ease of finishing: if the acoustics are assembled carefully, bringing it to a nice eco-look will not be difficult. Instead of increasing the thickness, it is recommended to add (glue) with reverse side another sheet of less resonant material, for example, the same MDF, to make a “sandwich”. Most good option applications of the array are “shield” type acoustics, where a beautiful and heavy front panel is required.

Exotic. Often the choice is determined by what is on hand. Just as a bird can masterfully weave all kinds of garbage into its nest, so a music lover drags everything that is in bad shape. You can find ideas on the Internet made from plumbing pipes, artificial stone, papier-mâché, cases and cases from musical instruments, primitive building materials, IKEA products, etc., etc.

Where should I put the speaker?

The main task of acoustic design can be formulated in simple language approximately like this: to maximally separate the vibrations emitted by the front side of the speaker cone from the same anti-phase vibrations emitted by the rear side of the cone. From the point of view of the textbook, the ideal acoustic design is considered to be an infinite screen, such an incredibly huge shield in which the speaker is installed. It’s clear that the words “incredibly huge” do not fit either our home or our salary, so engineers began to look for a way to “minimize” this screen negative consequences for sound. This is how all the variety of options turned out, some have gained the most widespread fame on the Internet, and we will consider them in this article.

Just a speaker or housing without housing

It’s hard to imagine that there is such a type of “acoustics”, but, scrolling through the feed of photos on Pinterest on the topic of audio, I increasingly come across clusters of 12-inch speakers that are assembled together without any design and clearly represent a complete unit. Probably, the author’s intention is permeated with the following logic: any housing spoils the sound, an acoustic short circuit is better than wooden shackles, but in order to have at least some kind of “low”, you need to take speakers with the maximum cone area for which you can only afford enough money. If this is your path - no comments.

Shield and “broadband”

They say that those who have tried a lamp, a full-range speaker and open design, will never return to the traditional, transistor-rubber lifestyle. Describing the properties of a shield is not a rewarding task; all the necessary information is in the archive, and for the laziest - on YouTube, where they explain in detail what kind of animal it is and what it is eaten with, for example:

The biggest advantage of this design is its ease of manufacture. You need a sheet of your favorite material and a jigsaw. The most important criterion that will influence the final sound quality is the cost of the installed dynamic head. The 4a32 speaker has gained unabated popular fame, even such grandees as fostex, sonido, supravox, sica or the visaton B200 itself are left far behind. The saying “size matters” is the best mathematical formula for a shield (the bigger the better). Next come variations of the shield, for example, a shield with folded side walls, a shield in which the low-frequency module is made in the form of a box with a bass reflex, etc. The signature feature of the sound is an “airy” sound with a minimum of resonances, and at the same time a relatively high sound pressure.

PAS – acoustic resistance panel

What if you try to cross a shield and a closed box? You will get a box with a back wall in which many holes are made. The number of holes, their total area in combination with the volume of the box will determine the degree of damping (resistance), the level of low frequencies (the fewer “holes” - the more bass, but also the more “mumbling”). The quantity is selected experimentally, according to taste.

Linear array of emitters, group emitter (GI)

In fact, this subtype of acoustics concerns more the speakers than the design of the cabinet itself. I think you've already seen columns, each of which consists of large quantities identical small-small speakers, or not very small ones, as your budget and living space allow:

According to the electrical diagram, the heads are connected in series, that is, the “plus” of the previous one is connected to the “minus” of the next one, it is possible to combine a series-parallel connection. The number of speakers, in fact, is also limited only by money; common sense, as a rule, by this moment disappears without a trace. Don’t think anything bad about me, I tried such a perversion, I even liked it, if possible, I strongly recommend assembling a similar structure for yourself, at least for the sake of interest. Again, the budget for this outrage is not very large; as a rule, domestic speakers are used in good condition, 5gdsh, 8gdsh, 4gd-8e, etc.

Acoustic design - the same shield or closed box, preferably of a tricky shape, for example triangular. One of the problems to be faced is the high total resistance; not every amplifier will reveal the potential of the “array”. Serial samples produced at the factory have more complex solutions; speakers are often assembled into clever modules, and filters are added.

Bass reflex,bassreflexport, Helmholtz resonator, also known as a box with a “pipe”

Here it is - the most popular acoustic design option. The most favorable price/result ratio becomes widespread; our case is no exception for of this rule. For those who haven’t downloaded the archive of an unknown audiophile, we’ll explain it in layman’s terms. There is a certain volume of air in the bass reflex pipe, which depends on its length; it is also “connected” with the air contained inside the speaker. With successful adjustment of the pipe length (let's not dive into theory right away), it is possible to achieve more confident reproduction of low frequencies than just in a closed box. To put it even simpler, with a bass reflex you get deep bass. For a more in-depth understanding, here is a video from a channel we already love:

Although this type of acoustics is popular, it is far from easy to manufacture; one thing leads to another. Speakers that are suitable for this design are called “compression”, most often have a rubber surround and a frequency band that requires the installation of a high-frequency link, tweeter or tweeter, that is, an electrical filter is added. Choosing the optimal volume of the housing, its geometry, and precise adjustment of the pipe length have great importance and do not always correspond to the calculated values. The situation is made easier by the presence of a mass of projects on the Internet, where the authors have already passed the thorny path and offer step by step instructions with a detailed description of what, how, and what needs to be made. However, there are always enthusiasts who are not satisfied with what is “ready-made” and have the tenacity to go their own way. The disadvantages of the bass reflex are “mumbling” and “crushed middle”. The first is solved by careful selection of the shape, diameter, material and length of the pipe; the second is by adding a separate mid-frequency section. The right path to three-way acoustics.

Reverse hornTQWP and other labyrinths of fate

What people haven’t come up with to complicate the path of vibrations coming from the back of the speaker... Perhaps the company that distinguished itself most of all was B&W with its Nautilus, at least erect a monument to this mutant sea shell. But these are grandees, and all we, ordinary audiophiles, can do is remember our nightmares and place boards with nails inside the rectangular box so that this vile sound doesn’t seem enough. Seriously though, there are speakers for which the “bass reflex” type design does not suit, and the shield does not provide the desired amount of bass, and the sight of the subwoofer makes something clench in your stomach. Then a reverse horn or more comes to the rescue difficult option– labyrinth. For those who are interested in how it works, we wish you pleasant viewing.

Someone may object: a reverse horn is not exactly a labyrinth, we can partly agree, but what is more reliable is that it is closer to labyrinths than a classic horn:

It reminds me of an old gramophone. As you can guess from the name, a reverse horn or labyrinth is far from the simplest type of acoustic design; it requires a good understanding of the theory, accurate calculations, or at least compliance with factory recommendations. For example, large manufacturers of wideband speakers, as a rule, provide a couple of variants of housing drawings in the documentation for their speakers.

Onken, closed box (CB), horn, passive radiator and others

Our narrative follows in the footsteps of popular popularity, and this is a rather narrow list. A closed box almost always mumbles, it’s difficult to find a speaker for the onken, the horn is large in size, difficult to manufacture and calculate, the passive radiator works well, but for some reason it has not taken root in amateur designs. You can probably find several more rare types or subtypes of design that are not mentioned here, but what can you do, you can’t cover everything.

Damping, "stuffing", "plug"

The cases are ready, what to do with them next? That's right, damping. Damping can be divided into two types: vibration absorption and sound absorption. Automotive materials, mastics and special sheets with an adhesive layer are well suited for vibration absorption, the latter being preferable. With sound absorption there is confusion and swaying, some people like felt, others like wool, batting, padding polyester, etc. The answer is quite simple - for different effects, depending on the type of housing and the frequency that you want to suppress, the choice of material will depend. Filling the case with sound-absorbing material increases its virtual volume, however, in my opinion, it is impossible to determine a universal norm.

Setting up the crossover (crossover filter)

You decided to make multi-band acoustics. Is a measuring microphone necessary? If this is a one-time project, then no, it is not necessary, it is enough to have a test selection of tracks and some experience to understand which sound can be called more correct. You’ll just have to go through the details of the passive filter longer, listen and compare, but in the end the result will be exactly what your ears and the room need. The situation is a little easier with active crossovers. Previously, you had to make them yourself, etching and routing boards, soldering, a very tedious process, especially if the circuit has a decent slope of cut and adjustment, for three-way acoustics it’s just a wild thing. Fortunately, today you just need to go to ebay and choose an option that suits your budget, whether you want it on op-amps or on DSP. You can smoothly adjust the frequency, and sometimes the slope of the cutoff (in especially rare cases, the phase), even every day.

The final

Sometimes it seems to me that the situation in the audio world is reminiscent of the legend of the Tower of Babel. Once upon a time, in distant times, when Van Den Hul's foot had not yet set foot on the ground, people built together one set of home stereos. Large, large speakers, an equally large amplifier, and thick, thick cables stretched to them. Someone from above saw this and was horrified - what a joke, if only they had read some books... Severe punishment befell the unlucky audiophiles, since then they have been arguing until they are hoarse, but they still cannot agree on how to make amplifier speakers, so everyone makes their own , how can.

Acoustic design does not mean decorating the speakers with carvings in an antique style, although this will give the speakers uniqueness, but solving the problems of acoustic short circuit.
The fact is that when the diffuser moves on one side, a overpressure air, and on the other hand the air is discharged. For sound to occur, it is necessary that air vibrations propagate into space and reach the listener, and in in this case the air vibrates around the dynamic head basket and the sound pressure it creates is not very high, especially in the low frequency region:

More details about the principle of operation of the dynamic head HERE.
Methods of breaking the acoustic circuit are called acoustic design, and each of them is designed to make it difficult for air to penetrate from one side of the diffuser to the other.
There are several main options for breaking an acoustic short circuit. The simplest one is to use sheet material in the middle of which a hole is cut for the dynamic head. This is called an acoustic screen:

A little more the hard way- open box, i.e. drawer without back wall:

Both of the above methods have too little efficiency, so they are practically not used only in cases where “there is no fish and no cancer.”
It is much more effective to use a closed box, and in such speakers special attention is paid to the tightness of the box - any gap in the box will produce overtones, since enough noise occurs in the box high pressure(when the diffuser goes inside the box), and a fairly large discharge (when the diffuser moves out):

The next option for acoustic design is a box with a bass reflex:

In this case, this is a rectangular hole located in a strictly calculated location on the front panel of the speaker system. However, this option can also be done using a pipe:

The advantages of these options include increased output at the frequency at which the bass reflex is designed, the main purpose of which is to invert, i.e. change the phase to the opposite. As a result, sound is emitted into space not only by the front part of the diffuser, but also by the rear part, the phase of which is changed by the bass reflex.
A more complex version of acoustic design is an acoustic labyrinth. The essence of this option is that the passages inside the speakers are located in such a way that resonance occurs at a certain frequency and, as a result, a large increase in output at this frequency. The calculations and manufacturing accuracy of such systems should be taken VERY seriously, since there is a high probability of “standing” waves occurring in the labyrinth. In this case, the sound quality will be even worse than that of the option with an acoustic screen:

The horn version allows you to get even greater output at the resonant frequency:

The difference between a horn speaker and a labyrinth speaker is that the direction of sound waves varies according to different laws - the horn either expands conically along its entire length, or exponentially. The labyrinth can have the same window along its entire length, it can expand or, on the contrary, narrow, but always linearly. In addition, for speakers with a labyrinth, both the front and rear parts of the diffuser take part in the work, while for horn speakers, both one and both sides can radiate.
The next acoustic design option is a bandpass or bandpass resonator:

This option differs from all previous ones primarily in that it emits only at the resonance frequency and requires strict adherence to the design dimensions.
The last three options are mainly designed for using a low-frequency dynamic head, while the previous ones are quite suitable for wideband speakers. Therefore, if the acoustic system has, in addition to woofers, others, for example, midrange and HF, then it is not recommended to embed them into the housing with the woofer.
In any case, to calculate the speaker sizes, you will need the characteristics of the dynamic head, in particular the Thiel-Small parameters. If this data is not available, it is necessary to obtain it before calculating the dimensions of the speaker housing.
There are quite a lot of descriptions of methods for obtaining these parameters - just use any search engine.
Of course, these are not all types of acoustic design - these are the most popular.
The enclosure dimensions are calculated using special programs for calculating speaker enclosures. Finding them on the Internet, as well as instructions on how to use them, is also not problematic.

When designing speakers, you should take into account some technological features - if the front panel on which the speaker is installed is recessed into the housing, then you will need to make additional ribs into which the front panel will actually rest:

If you don’t want to mess around with the ribs, you can make the front panel so that it rests against the sides of the case, which also strengthens the connection between the front panel and the sides:
You should also not forget about the methods of attaching the dynamic head to the front panel and the pitfalls that you may encounter. Mounting the speaker from the outside is most preferable, since it does not mechanically weaken the structure, but this method involves chamfering along the diameter of the dynamic head and sinking the speaker inside the body so that ALL emitters, bass, midrange, and treble are in the same line. chamfering reduces mechanical strength front panel and to restore it you will need an additional ring secured from the inside. The relevance of this ring is the higher, the greater the power expected to be obtained from the speaker being manufactured, and at powers above 150 W it is already 100% necessary:

If necessary, you will need to remove the side chamfers on the ring so that it does not interfere with the front panel installation into the case itself.
When installing the dynamic head, it is necessary to ensure that there are no gaps. If the chamfer is removed by a machine, the surface turns out to be relatively smooth; all that remains is to sand it. However, at home it is quite difficult to obtain a flat surface. It is not entirely clear what the manufacturers are doing here - it is strongly recommended to install the speaker from the outside, but the sealing rubber on almost all dynamic heads is located for installation from the inside:

To solve sealing problems, you can use door seals - self-adhesive strips foam rubber, sold in all hardware stores.

The sealant is glued along the perimeter of the chamfer and when installing the speaker, it completely fills all the cracks:

If the dynamic head is installed from the inside, then the hole will need to be chamfered to prevent the appearance of standing waves. However, such a chamfer weakens the rigidity at the point where the speaker is attached to the panel (the material is too thin) and this method of fastening is not acceptable for powers above 50 W without additional reinforcement of the structure:
It is advisable to use natural material for the manufacture of speaker cabinets, optimally plywood, but this material is too expensive. Therefore, it is better to use plywood to build speakers of medium and high price categories, using dynamic heads of VERY good quality and power above 100 W.

For powers up to 10 W, plastic is also quite suitable, but also using technological tricks.
The first problem when making speakers from plastic arises when eliminating the chatter of the plastic itself, especially manifested in the centers of the sidewalls. You can get rid of this unpleasant sound by using thicker plastic, or you can glue additional stiffeners. If the plastic is dissolved with dichloritane, then dichloritane with plastic chips dissolved in it can be used to attach the ribs. If the plastic is not dissolved by dichloroethane, then it is better to use epoxy glue, preferably made in Dzerzhinsk. Before gluing, carefully sand the contact areas with coarse sandpaper and do not be afraid that the glue forms beads at the point of contact of the parts to be glued:

For greater efficiency in suppressing overtones of the body, you can “paint” the resulting “baths” in 2-3 layers with anti-gravel - a coating used to cover the underbody of cars to protect against small gravel.

After drying, anti-gravel acquires the properties of rubber and absorbs sound quite well.
When using fiberboard as a material for the manufacture of speakers, it is necessary to determine the required thickness. If the speaker power does not exceed 5 W, then fiberboard can be used in one layer.

If the speaker power is higher than 10 W, but less than 20, then it is better to glue the fiberboard in half - first the sheets are glued together, and then the finished case is assembled:

For powers up to 30...35 W, you will need to fold the fiberboard in three or use 18 mm thick chipboard (unfortunately, 22 mm thick chipboard can only be found in old grannies in the form of old wardrobes made before the 80s). To stiffen the sidewalls, you can use spacers of the "CROSS" type:

For powers up to 50 W, the relevance of using fiberboard is already debatable - it is much easier to work with chipboard, MDF or plywood than to fold fiberboard from 4-5 layers. For this, material with a thickness of 18 mm is suitable, but you will have to use additional bars to ensure a greater connection between the speaker parts:

The speaker can be assembled using self-tapping screws, but since the power is not greater, it can be glued with epoxy glue or PVA, but it is better to buy it not at an office supply store, but at a hardware or construction store. This PVA will be called MOMENT-STOLYAR, water-dispersion glue. Buy on the market Recommended only in summer - after freezing the glue seriously loses its quality. However, to ease your conscience, it is better to screw at least a couple of screws into each block.
When manufacturing speakers, sometimes they make a serious mistake - the mid-HF link is not acoustically protected in any way from the impact of the back side of the woofer cone, which leads to a decrease in the efficiency of the speaker itself, and often the failure of the midrange link - too strong air impacts from the back side of the woofer diffuser lead to the midrange speaker coil being pushed out of the magnetic gap and the coil jamming.
Much more often they forget to subtract the volume of the protective casing of the midrange-high-frequency speakers from the total volume of the speaker; as a result, the internal volume of the speaker is less than necessary and the final characteristics are greatly blurred - the resonant frequency of the phase interferors increases noticeably, which results in unwanted overtones.
When assembling speakers with a power of up to 100 W, you can also use either chipboard or plywood 18 mm thick, although of course it is better to look for material 22 mm thick. To eliminate the occurrence of resonances in the sidewalls of the speaker body, additional support bars are also used through which parts of the speaker are attached. It would not be superfluous to install a “cross” and an additional washer for attaching the woofer dynamic head, as well as treating the speakers from the inside with sound-absorbing materials, for example, pasting with paralon or foam plastic 5-10 mm thick, just do not forget that the pasting will “eat” part of the internal volume and it is necessary to make an adjustment for it when calculating the dimensions of the body.

The best results are obtained with polyurethane foam, since the thickness of the applied layer can be adjusted by the speed at which the foam is released from the can. If the foam is released VERY slowly, then it turns out to be very dense and the increase in volume is not very large. If the foam is released VERY quickly, then it turns out to be much looser, and when it hardens, it greatly increases in volume. If foam is applied to the sides of the case from the front panel, increasing the foam output as it approaches the rear wall, and ensuring a minimum rate of foam output at the front panel, the internal volume of the speaker will take the shape of a pyramid lying on its side. Such tricks make it possible to completely solve the problems of standing waves, since there are no parallel planes, and the unevenness of the frozen foam only enhances the pyramid effect. When using this technology, you should be more careful when calculating the dimensions of the workpieces - the internal volume decreases VERY significantly and this requires a serious increase in the speaker body.

It is recommended to glue the ribs for fastening the sidewalls, in addition to the screed with self-tapping screws, as in the previous version, but there are several more options for adhesive masses:
- epoxy glue mixed with fine sawdust, or, better yet, wood dust;
- MOMENT-JOINER, but before screeding, the applied glue must be allowed to dry a little until it reaches the consistency of butter room temperature. This will allow you to more completely fill with glue all the irregularities between the speaker parts;
- polyurethane glue, for example MOMENT-CRYSTAL, which also needs to be allowed to dry a little. After assembly, the gluing area must be thoroughly heated with a hairdryer, which will lead to the formation of small bubbles in the adhesive mass, and the mass itself will more tightly fill the unevenness between the contacting parts of the body;
- automotive sealant of domestic production, precisely domestic, since after hardening it is much tougher than imported sealants;
- mounting, polyurethane foam. Before applying it to the parts to be glued, the foam is “released” onto an unnecessary piece of plywood or fiberboard, and then thoroughly mixed with a metal spatula until it “shrinks,” i.e. until you obtain a mass similar in thickness to thick sour cream. After application and screeding, the foam will still expand slightly and completely fill all the irregularities at the point of contact between the speaker parts.
After gluing, the parts should be allowed to dry thoroughly for 20...26 hours.
To increase the volume at the same output power, you can use “double” dynamic heads - parallel or series connections of two identical speakers are used for the low-frequency section. In this case, the total area of ​​the diffusers increases, therefore the speaker can interact with a much larger amount of air, i.e. create greater sound pressure and this makes the subjective loudness much higher:

It should be noted here that the use of a large number of speakers, including for dividing the audio range, begins to introduce some troubles - it is quite difficult to achieve signal phasing in those places where the frequency response of speakers neighboring in the range intersects. Therefore, you should not chase a large number of bands for a homemade speaker - this mess can be very spoiled with such oil.
It is better to make speakers with a power from 100 to 300 W from plywood, and you will have to look for plywood with a thickness of 22 mm. The speaker is also assembled using stiffening bars that are glued. It is better to give the bars the shape of equilateral triangles, where the legs will be attached to the sides, and the hypotenuse will be directed inside the body.
If you cannot find plywood of this thickness, then you can use 8 mm thick plywood glued in three - the final thickness of the material is 24...25 mm. The adhesives are listed above.
As technological advice, we can only recommend first cutting the necessary blanks and only then gluing them, and immediately tightening them with self-tapping screws.
When installing a “cross” inside the AC, which would not be amiss, it is better to round the corners of the tie bars - quite large volumes of air are already moving and turbulence may occur around the right corners of the screeds.
It is also recommended to “round” all internal corners using plasticine or applying several layers of thick anti-gravel.

Another type of acoustic design is separate housings for each speaker. These speakers do not use passive filters, and the signal is divided into ranges immediately after the amplifier's volume control.
The split signal is then fed to three separate power amplifiers, which each drive their own speakers:

It would be unfair not to mention the “fillers” often used in speakers - small rollers of sound-absorbing material lying inside the speaker. Such rollers make it possible to slightly increase the calculated internal volume of the body, however, in order to correctly manufacture such a “filler” it is necessary to know its acoustic properties. Obtaining the characteristics of the “filler” in a home-made environment is quite problematic, so the only thing left to do is either refuse to use the “filler” or experimentally find out the required volume and the material used (usually fluff wool, batting, sentipon). At powers above 100 W, it also becomes important to ensure the stability of the speaker cabinet, since quite a lot of work is already being done to move the diffuser and the air is actively “resisting”. It is also advisable to break the mechanical connection between the bottom of the speaker and the floor on which the speaker is installed. For these purposes, they usually use either tripods, which are problematic to make at home, or they use steel spikes screwed into the bottom of the speaker: At powers above 200 W, it is desirable to strengthen the front panel of the speakers and it is desirable to use materials of different structures, for example, if the front panel is made of plywood, then with
For greater stability of the speaker, its mass can be increased by coating the bottom with polyurethane foam and laying a couple of bricks in it, covering them on top with the same foam.
After the foam has hardened, it is better to cut off the irregularities with a stationery cutter. The “stolen” internal volume must be taken into account when calculating the size of the future speaker.
For powers above 200 W, it is better to use combination materials - all speaker parts are glued together from 18 mm chipboard and 18 mm plywood. Plywood is used as the outer layer and chipboard as the inner layer. This trick allows you to save a little - chipboard is much cheaper than plywood. It is advisable to glue the inside of the speaker with sound-absorbing material, for example, triple-sewn batting, double-stitched with quadruple padding (the padding can be double and quadruple), 5...10 mm polystyrene foam. The different structure of tightly glued materials of different structures eliminates the problem of resonance of the body itself.

It is better to additionally tighten the corners with metal corners - this will add rigidity to the structure and protect the corners of the speakers from damage - the speakers are already quite heavy and during transportation various impacts are possible from which the corners most often suffer.
For powers closer to 1000 W, the thickness of the material should already be quite large, for example, two layers of 18 mm plywood plus a layer of 18 mm DPS for a total of 54 mm, and the DPS is glued between the layers of plywood, however, the speakers already move into the category “for sound”, therefore quality can be sacrificed in favor of mobility. Based on this, you can use double 18 mm plywood, installing a “cross” inside.
A microphone attached to the speaker (the membrane hole to the body) and connected to any linear amplifier on the oscilloscope screen will draw both the moment of impact and the aftersound that the body itself gives. The test is, of course, quite crude, since in reality the “shock wave” comes from the inside, and during the experiment from the outside, however, based on the results of this test, one can judge at what frequency the body itself resonates and how quickly attenuation occurs:

An ideal speaker does not cut and the moment of impact fades immediately, almost instantly, but the walls of an ideal speaker consist of concrete 1 cm thick for every watt of power and such a speaker is more suitable for ridicule than for use:

The finishing of the speakers can be very different, there are no strict requirements here. If the body is made of plywood and the pattern is quite attractive, then the body can be sanded and then coated several times with colorless varnish:

You can buy veneer from valuable wood species and cover the speakers with veneer to match the color of the furniture in the room:

Car audio stores sell so-called acoustic fabric, which is synthetic felt. The material adheres well and stretches, which will allow you to finish the speaker with a fairly:

high level

Having sanded the body, you can paint it with car paint, just make allowance for the fact that car enamels need to be dried at high temperatures. Therefore, you will have to use a special hardener "IZUR", the mixing proportions are written on the packaging of the hardener, although it is better to add 10-15% more than the suggested proportion:

If the body is carefully sanded and sanded, then it can be covered with a self-adhesive film sold in BOI stores, but this material is quite delicate and should be used if you are sure that the speakers will stand in their place for ten years:

If you plan to frequently transport the speaker system, it will be very useful to provide appropriate handles.

This is especially true for small speakers, which you want to take two at once, and for large ones, which simply have a lot of weight.

How to independently assemble an active speaker with increased efficiency at low frequencies is described.

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There are special requirements for computer speakers. You can also make a model for your car or studio yourself. In this case, it is very important to follow the instructions. First of all, for assembling speakers you should consider standard scheme models.

Speaker layout

The speaker circuit includes speakers, pads, diffuser and crossover. Powerful models use a special bass reflex. Amplifiers can be installed with field-effect or switching transistors. To improve sound quality, capacitors are used. The woofer is matched with the amplifier. The dynamic head must be attached to the seal.

Single speaker models

Single speaker speakers are very common. To assemble the model, you will first have to deal with the body. Plywood is often used for this purpose. At the end of the work it will have to be sheathed. However, the first step is to make the side posts. For this purpose you will have to use a jigsaw. you can choose a small power.

The inside of the plywood is necessarily stitched with vibration-proof tape. After fixing the speaker, the seal is fixed. Glue is used for this purpose. Next, all that remains is to attach the diffuser. Some people make a separate shelf for it and fix it with stacking screws. To connect the speaker to the plug, a terminal block is installed. How to turn on speakers? For this purpose, a cable is used from the terminal block, which should lead to a power source.

Model drawing for two speakers

Speakers with two speakers can be made for home or car. If we consider the first option, then a pulse type diffuser will be required. First of all, durable plywood is selected for assembly. The next step is to cut out the bottom post. Models with legs are very rare. To cover the veneer, you can use regular varnish. There is no need to glue vibration isolation tape to the front pillar. The diffuser is mounted under the speaker. To make a hole in the panel, you need to use a jigsaw. The bass reflex is fixed at the rear wall. Some manufacture devices with horizontal speakers. In this case, the diffuser will be located at the top of the structure. Wires for speakers are of the two-core type.

Devices with three speakers

Speakers (homemade) with three speakers are very rare. These devices are most suitable for the multi-channel type. To assemble the model, first of all, sheets of plywood are selected. Some also recommend using veneers. However, models from natural wood They are quite expensive on the market. The speakers should be installed horizontally. The device will also require an amplifier.

Metal corners are used to secure it. To connect the plates you will need tightening screws. In some cases, the plates are secured with glue. Next, the model will have to be partially covered with leatherette. The next step is to install the terminal block. In order to fix it on the body, you will need to make a separate hole. It is also important to note with regulators. Microcircuits for them are used of the capacitor type. When the speakers produce noise, you need to change the diffuser.

Studio devices

Speaker drawings for studios assume the use of powerful speakers. The diffuser is most often used of the pulse type. Many experts recommend installing two amplifiers. For normal operation you will need a zener diode.

In order to assemble the speakers yourself, the housing is first made. On the front panel for the speakers are made round holes. You will also need a separate output for the bass reflex. The design of the columns is quite different. Some people prefer to varnish the surface of the case. However, there are models covered in leather.

Models for computers

Speakers for computers are often made with one speaker. To assemble the model, veneer sheets of small thickness are selected. A hole for the speaker is cut out on the front panel. The bass reflex must be located at the rear of the housing. If we consider low-power models, the amplifier can be used without a resistor.

To adjust the speaker volume, special crossovers are used. These elements are allowed to be installed on a bass reflex. If we consider devices with a power of more than 100 W, then amplifiers can only be used with resistors. Some people select pulse diffusers for the model. At the end of the work, the terminal block is always installed.

Automotive modifications

Available with two or three speakers. To assemble the model yourself, you will need sheets of plywood. In some cases, varnished veneer is used. To fix the speaker, you need to make a hole in the panel. The next step is to install the bass reflex. Some modifications are made with low-frequency cores. If we consider speakers (homemade) of low power, then the bass reflex can be installed without an amplifier.

In this case, a multi-channel crossover is used to control sound. Some specialists install terminal blocks behind the bass reflex. If we consider speakers with a power of more than 50 W, then the microcircuits are used for two amplifiers. The diffuser is installed as a standard pulse type. Before fastening the case together, it is important to take care of the vibration-proofing layer. For the terminal block, you need to make a separate hole on the plate. Some people believe that the body must be cleaned. The wires for the speakers are of the two-wire type.

Open-back speakers

Portable speakers with an open case are quite easy to make. Most often they are made with one speaker. Holes are made on the back panel of the device with a drill. The plates are directly connected with tightening screws. The diffuser for such devices is suitable for pulse type. Bass reflex units are often installed with one amplifier. If we consider powerful portable speakers, they use a resistor crossover. It is attached to the bass reflex. Many experts recommend installing speakers on a seal.

Devices with closed housing

Speakers (homemade) with a closed housing are considered the most common. Many experts believe that they are the best in sound quality. Bass reflex devices for devices are suitable for the operational type. The woofers are installed in the holes. For the purpose of assembling the case, ordinary sheets of plywood are suitable. It is also important to note that there are modifications with cores. If we consider high-power speakers, the terminal blocks are installed in the lower part of the housing. The design of the models is quite different.

20 W models

Assembling 20V speakers is quite simple. First of all, experts recommend preparing six sheets of veneer. They should be varnished at the end of the work. It makes more sense to start assembly by installing the speakers. The bass reflex is used as a pulse type. In some cases it is installed on pads. Experts also recommend using rubber seals.

Power supply to the speakers is provided through the terminal block. It is attached to the rear panel. The bass reflex can be installed either with or without an amplifier. If we consider the first option, then the cores are selected of the phase type. In this case, the woofer does not need to be used. If we consider speakers without an amplifier, then they use a crossover. At the end of the work, it is important to clean the body and varnish it.

50 W devices

Speakers (homemade) rated at 50 W are suitable for ordinary acoustic players. In this case, the body can be made from ordinary plywood. Many experts also recommend using natural wood veneer. However, it is important to note that he is afraid of high humidity.

After choosing the material, you should work on the speakers. They must be installed next to the bass reflex. In this case, you cannot do without an amplifier. Many experts recommend selecting only low-frequency crossovers. If we consider modifications with a regulator, then they use a pulse diffuser. The terminal block in this case is installed last. You can always use leatherette to decorate the speakers. More simple option is considered to be coating the surface with varnish.

Speakers with a power of 100 W

100 W speakers are suitable for powerful ones. In this case, the bass reflex is taken only of the pulse type. It is also important to note that the amplifier is installed with a crossover. Many experts recommend using veneer to assemble the case. It is better to install the woofer on a pad.

A characteristic feature of counter-aperture is that the sound coming to the listener from virtually all directions, although it creates an impressive presence effect, cannot fully convey information about the sound stage. Hence the stories from listeners about the feeling of a piano flying around the room and other wonders of virtual spaces.

Counterperture

Pros: A wide zone of spectacular volumetric perception, naturalistic timbres thanks to the non-trivial use of wave acoustic effects.

Minuses: The acoustic space is noticeably different from the sound stage conceived when recording the phonogram.

And others...

If you think that this is the end of the list of speaker design options, then you greatly underestimate the design enthusiasm of electroacoustic speakers. I described only the most popular solutions, leaving behind the scenes a close relative of the labyrinth - the transmission line, the bandpass resonator, the housing with the acoustic resistance panel, the load pipes...

This kind of exoticism is quite rare, but sometimes it materializes in a design with a truly unique sound. And sometimes not. The main thing is not to forget that masterpieces, like mediocrity, are found in all designs, no matter what the ideologists of a particular brand say.

Acoustic speakers

The sound quality in the car directly depends on the location of the speakers. In addition, the resonance of the housings is also important in this matter.
Therefore, the body of the speaker used in this case must be made of a material that has sufficient resonance. As a result of this, the most suitable option will be - creating speakers with your own hands.
You can learn how to make acoustic speakers yourself from our article. The information will help you learn not only how to make speakers yourself, but also how to assemble a real speaker system.

Creating Column Conditions

First of all, you need to find out what size the column will be. To do this, you need to decide on its location.
Most often, the speaker is installed in the trunk, since there is enough space for it to have enough space. In addition, a kind of resonance is also created in the luggage compartment, so the music sounds a little different here.
You can also install the speakers near the rear window, but here they will have to be more compact in size, since massive speakers may not fit here.

Note. However, this again depends on the position of the column: standing or lying down.

Dimensions

To find out the size of the speaker box:

• Decide on its location.
• Determine how much space can be allocated for installation.
• Measure the size of the allocated area.

Note: 30 cm in length is sufficient for a speaker in the luggage compartment. But the speakers installed behind back seat should not be more than 15 cm.

Material selection

• Chipboard. By the way, this material can be found much easier than others, since it is often found on sale. In addition, its price is quite affordable.
  Advantage of this material is that it has quite a large output, so the sound of the speakers will not be distorted. This material is also the lightest, so the structure will not be too heavy.
• Hard rubber (ebonite). The products come out pretty good, but the sound will be a little muffled. And finding rectangular pieces of ebonite on sale is not so easy.
  In addition, the product may have bad smell. The most important advantage: ebonite is difficult to ignite, so the speaker housing will not burn out in the event of a short circuit.

• Wood. Wood will do any tree.
  In this case, it is better to give preference to oak or pine, since with their help you can create a good resonance. Another advantage of the material is its attractive appearance.

Note: this product can even be painted, so it will turn out very beautiful.

Creating a Corpus

The body can be made in any convenient way.
The most suitable option is the following:

• Using a hacksaw, cut out parts from the material.
• Select the parts to which the speakers will be attached. Round holes should be made in their central part.

Note: The diameter of the hole must match the diameter of the bottom of the speaker.

• It is also necessary to cut out small rings that will be attached to the bottom of the holes made (so that the speaker is securely fixed). The shape of these rings should resemble a plate without a bottom.
• Glue the rings to the parts.
• Around the rings in the parts, make more holes in the shape of a triangle with rounded corners.

Note: this is necessary so that the sound penetrates into the housing, and does not just go out.

• For the inside of the case, small partitions should also be made (their length should correspond to the length of the case itself). With their help the bass reflex will be held.
• Make small ports through which the terminals will be secured.

Column assembly

To assemble all the parts into one whole, you should:

• Connect the body parts using glue or self-tapping screws: rectangular parts on the sides, bottom part, as well as a part with a hole at the top.
• Fill the inside of the column with synthetic down.
• Place the speaker in the intended place.

Note: The speaker wiring can be removed through any hole that is conveniently created.

• Paint the frame with varnish. This way it will have a finished appearance.

Note: it is not necessary to use varnish for painting. Black paint may be useful for this. And some details can be done in a different color altogether.

Creating a speaker system

The sound system does not always indicate the presence of speakers.
You can work on creating a sound system in a car like this:

• Make podiums from foam. For this:
• Make a template from cardboard. Attach it to the place where the podium should be.
• Using the template, cut out the base for the podium. For this purpose, ordinary plywood and reinforcement can be useful.
• The base consists of two rings. In this case, the diameter of the first ring must correspond to the diameter of the protective mesh. But the diameter of the second is the diameter of the column.
• The rings must be connected to each other using self-tapping screws.
• Cut six blocks to create a slope. Glue all the parts together.
• Pour into the frame polyurethane foam and leave it like that until it dries.
• It will turn out more interesting option, if instead of plywood you use small pieces of various types of trees. In this case, you should select dry pieces of wood that do not have cracks. Everything on top should be thoroughly varnished to make the structure more reliable. For greater efficiency, everything can be secured using two slats.
• Mount the speakers into the sockets and install the podiums.

Thus, you can create acoustic speakers (see) right at home and with your own hands. The price of such pleasure will not be high, since you will only need to spend money on purchasing the material.
And in general, you can use any old speakers. The main thing is that they work and are in good condition.
Of course, before starting this process, it is worth reviewing various photos and videos on this topic. The instructions will also be useful.