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The better to fill homemade acoustics. Floor standing three-way speakers. Creating a speaker system

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We open a popular magazine about good sound and look with pleasure at the elegant images (if not the image) speaker systems, but there is something to see. 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, made of 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”. Basic Rule– 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 wood valuable species 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) another sheet of less resonant material on the back side, for example, the same MDF, to make a “sandwich”. The most successful option for using the array is in shield-type acoustics, where a beautiful and heavy front panel is required.

Exotic. Often the choice is determined by what is at 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?

Main task 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 wages, so engineers began to look for a way to “minimize” this screen with minimal 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 one is better short circuit than wooden shackles, but in order to have at least some “lower”, you need to take speakers with the maximum diffuser area that you can afford. If this is your path - no comments.

Shield and “broadband”

They say that those who have tried the tube, 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 quantity identical small-small speakers, or not very small ones, as your budget and living space allow:

By 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 in good condition are used, 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:

Though this type acoustics and popular, it is far from being so 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 electric 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 detailed description what, how, from what should 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. Right way 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 might guess from the name, a reverse horn or labyrinth is far from the simplest type of acoustic design; it requires good understanding theory, accurate calculation, 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 a few more rare species or subtypes of design that were not mentioned here, what to 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. Well suited for vibration absorption automotive materials, mastics and special sheets with an adhesive layer, the latter is 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 sound-absorbing material the body increases its virtual volume, however, in my opinion, it is impossible to determine a universal norm.

Setting up a 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.


Greetings to Datagor readers! I want to tell you about creating an acoustic system using 3D printing technology. Using a 3D printer, I was able to build an unusual acoustic system in the shape of a ball, as well as solve a number of additional problems that arise when making acoustics.
I would like to note that I am not at all advocating the use of plastic as the main material for building speakers.

Ever since my student days I had a dream - to make speakers in the shape of balls. But the methods of creating a case available to me at that time non-standard shape didn't inspire me at all. And now, many years later, I got a 3D printer.

Now here is my translation of Troels Gravesen’s article about “the world’s worst dome tweeter Philips AD 0160.” I think he didn’t come across Soviet, or even many modern tweeters.
Most likely, few people have this particular tweeter (tweeter, not to be confused with Twitter), but Troels’ research will be useful for home-made people to assess the quality and correct use tweeters.

Best regards, Sergei

I'll show you on real example, what can be done to old speakers, namely their drivers, to get improved sound.

Unfortunately, not every one of us can afford to have a high-quality speaker system in the house. Now even the most cheap option will cost at least 10 thousand rubles. However, why not buy low-quality speakers that make a squeaking sound? If you are so eager to have your own in your home, you can make it yourself.

Moreover, all suitable parts and elements can be purchased almost anywhere, and their cost will certainly not be 10 thousand rubles. How to do it yourself? You will learn about this from our article today.

Preparing tools

So, during the work we will need the following materials and tools:

  • screwdriver;
  • chipboard sheet or MDF (for making the speaker system housing);
  • marker;
  • jigsaw;
  • PC power supply 400 W;
  • radio;
  • Bulgarian;
  • a pair of acoustic speakers;
  • furniture screws and self-tapping screws;
  • sealant (it is best to use silicone based);
  • voltmeter and glue.

Before assembling, first check the operation of the radio and find out whether it can be powered or not. It is also necessary to test the speakers for sound quality. After this, you can safely begin manufacturing the housing and other elements of the speaker system.

Case manufacturing

As walls for the column, you can use a regular sheet of MDF or chipboard. In this case, it is unacceptable to use plywood, since according to its characteristics it is very flexible and produces a strong resonance. When making a housing for the speaker system, also take into account the fact that the more air remains inside the box, the softer the bass will be. Therefore, leave as much free space as possible, but everything should be in moderation (otherwise such speakers will simply be impossible to transport).

Place the shelf so that the maximum amount of air reaches the speakers. Next, mark the places for cutting with a marker. Now you can safely cut a sheet of chipboard with a jigsaw. We also note that the edges of the cut parts of the tree should be carefully aligned. To do this, use a small construction grinder. Please note that it can work with several discs - for metal and wood. We need last option, since when processing such materials, the cutting element of the first type simply wears off and even smokes. Experts recommend using a petal circle.

Now the matter remains small. On the body, mark places for screwing in furniture screws and use a screwdriver to screw them in completely. In the case of screws, first make markings for them and drill through holes. That's it, the housing for the speaker system has been successfully manufactured.

Wall fasteners

Emphasis should be placed on the strength of the wall fasteners. Don't skimp on screws and self-tapping screws. The design of the speaker housing should be as strong and durable as possible. If the number of screws is insufficient, the system walls will rattle heavily under heavy load, thereby only worsening the sound quality.

Thorough assembly

How do you make a three-lane with your own hands? After you have made the case (the so-called “monoblock”), you can begin to thoroughly assemble the structure. Here it is best to use a cordless screwdriver with a 4mm hexagon to tighten the screws. Remember that inside the speaker its own sound load is distributed from minimum to maximum - bottom wall, top, front and side.

How to do it yourself next? At the next stage, the joints should be processed silicone sealant. This is necessary in order to prevent excess from penetrating out of the case through the cracks. Thus, the level of music playback will become even better. How then do you make an acoustic system with your own hands? After lubricating all the cracks with sealant, you will need to install the speakers and radio. The latter is best purchased assembled. The speakers, together with the radio, are installed through holes made in the bottom wall of the monoblock.

When everything is ready, the final design should look like this: back side The monoblock contains a power supply, two speakers on the sides (each of them is located in a separate column) and a car radio in the middle. Making speaker systems with your own hands occurs in a certain order of actions - first the power supply is mounted, and then the radio tape recorder. This will make it much more convenient for you to screw fasteners. But at this stage, the PC has not yet been completely assembled. Next, you will need to reinforce the corners. We will tell you about this in the next section.

How to make a speaker system with your own hands? Strengthening corners

The whole essence of the work is pasting certain parts monoblock with subsequent installation of square or triangular beads on them. It is not necessary to use Moment as an adhesive. Regular PVA will do the job quite well. Before applying glue to the surface of the material, make sure that it is dry and that its surface is free of cracks and bends.

What needs to be done in order for the power supply to work?

To do this, you will need to put a jumper on the wide, large connector (in other words, short it). Here it is enough to use a regular paper clip. Use it to connect two wires (green to black) and check the functionality of the device with a voltmeter.

To ensure that these elements have greater conductivity, after installing the contact, thoroughly solder their connection points. Now insert the block body inside the monoblock and attach it with self-tapping screws. Also treat any resulting cracks with sealant.

About sound-permeable material

At the next stage, the acoustic system, made by yourself, is filled with a special sound-permeable material (here you can use ordinary padding polyester). They need to fill the entire volume of the columns.

However, you cannot apply it to the diaphragm. This sound-permeable material significantly reduces the load on the walls of the system and reduces the speed of sound waves. So, when playing a melody, the speaker design will practically not vibrate. However, you should not follow the principle “the more, the better.” If you overfill the speaker with synthetic padding, it may lose bass and, accordingly, the sound quality will deteriorate significantly.

Fan

If your TV or computer speaker system is designed for high output power, consider additional elements cooling.

Indeed, under high load, the elements of the speakers become very hot, which can cause their premature failure. And you need to install the fan in such a way that it blows from the inside to the outside, that is hot air took him outside (or room). If the heat from the radio is removed, overheating of system parts will be eliminated, and your speakers will last a very long time. long time. At this stage, the question of how to make a three-way speaker system with your own hands can be considered closed.

At first glance, making your own speakers is quite simple. However, this is misleading. First of all, it should be noted that the models are manufactured with various elements. Depending on them, the device parameters and sound quality will be different.

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 drivers, 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. 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, first of all you should make side racks. 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 back wall. Some manufacture devices with horizontal speakers. In this case, the diffuser will be located at the top of the structure. Speaker wires 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.

To fix it, use metal corners. 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.

With the aim of self-assembly For speakers, the body is first made. Round holes are made on the front panel for the speakers. 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 closed case 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 back 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 regular 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.