How to Build a Speaker Box

Speakers are one of the most popular audio devices, probably right after headphones. They come in all shapes and sizes and all of them have their own place in our cars, in our homes, offices, etc. Each of them has its own purpose and depending on that purpose, it has a specific build and size. You might think that the market offers anything you could possibly need but it wouldn’t be surprising if you couldn’t find the speaker you are looking for, especially if you’re looking for the speaker for your car.

One of the simplest but the least applicable solutions for this problem is to take some basic material, some basic tools, a woofer or two, and build a speaker on your own. If you think about it, this may be great not only because the speaker box dimensions will fit perfectly your car, living room, or any other place but also because you will learn something new, have fun making the speaker enclosure, and also save a lot of money.

If you stay with us, we will show you what kinds of speaker boxes there are and give you a step by step explanation on how to build a speaker box on your own in a few days. Don’t worry, it’s not so difficult and even the beginners can do it successfully if they try hard enough.

What Kinds of Speaker Enclosures are There?

Infinite baffle/free-air

Infinite baffle is actually not a real box, it is more like a board with holes where you put your woofers. It is perfect for car trunks because the trunk itself acts as the enclosure, isolating the sound from the back of the speaker. These “boxes” are the easiest to make, they occupy the least space and their frequency response is flat. They require less power than the others and produce the least distorted sound. However, they make it difficult to separate back and front sound waves and the woofers are completely exposed to damages.

Sealed/closed enclosure

Sealed enclosures are the smallest and the easiest to build. They consist of a closed air-tight box and a woofer, and they are perfect if you need a deep bass to fill out your car or your apartment. They also require more power than the other enclosures so it is recommendable to use them with amplifiers in order to get the best performance.

Ported/vented enclosure

These enclosures are called venter or ported because of the ports/vents they have in order to reinforce (enhance) the bass response. This is the most popular type of enclosure because it offers the most powerful sound, although it is probably one of the most difficult to build and it occupies more space. The speakers with ported/vented enclosures can deliver even deeper bass than the speakers with sealed enclosures.

Bandpass

When it comes to bandpass enclosure, the speaker (woofer) is hidden inside the box with two chambers while the sound comes through one or more ports. These enclosures can have one port (4th order bandpass), 2 ports (6th order bandpass) or 3 ports (8th order bandpass). These speakers deliver loud sound with a limited frequency range. However, they are very efficient and they are perfect for hard rock music, hip-hop or reggae, although they can get a bit boomy. They are also extremely difficult to build and can occupy a lot of space.

Materials Needed

No matter what type of speaker box you want to build, you will need the same materials and, as you will be able to see, all the things from our list are easily reachable and relatively affordable. Of course, the final cost will be lower if you have the necessary tools in your garage but in case you don’t, try borrowing it from a friend or neighbor.

Basically, the things that are essential for building any kind of enclosure are a jigsaw, table or circular saw, as well as an electric drill. You will also have to get a piece of medium density fiberboard (MDF) which is the best for building these boxes. The next thing you will need are different kinds of screws, glue or some kind of adhesive applicable to wooden materials, and some kind of insulation like fiberglass or polyfill. Also, you might need a piece of speaker cloth for the final touch and a few braces to fix and strengthen the box.

Building a Speaker Box

Before we start, we have to say that the shape and size of an enclosure affect and determine the sound quality and its color. They define how much power it will need and how deep the bass will be. You can’t build any speaker box without mathematical calculations and it is very important to do them accurately because even some minor flaws can affect the performance, especially with the vented boxes.

Step 1: Choose woofer/subwoofer and type of the enclosure

When you choose your new woofer/subwoofer depending on your needs and musical taste, you should pay attention to the manufacturer’s recommendations about the enclosure size and shape. Before you buy anything, think about the place where your new speaker box will be installed and what will be its purpose. Once you define the characteristics of the woofer and enclosure, you can pass to the next step.

Step 2: Making enclosure and calculating dimensions

Before you start cutting, make a model of your future box. You can do it on your computer or draw it manually with a pen and a piece of paper but the model should exist. Calculate the dimensions of the box based on the manufacturer’s recommendations. If you need more help, you can type into your browser Re Box Calculator and this program shall make it easier for you. However, you should determine the external box dimensions: minimum depth (add 2 inches to the subwoofer’s depth) and minimum height and width (measure the subwoofer’s diameter) of your speaker box. Also, don’t forget about the internal dimensions and the total box volume. In order to determine internal dimensions, take away the thickness of the wood from the external dimensions and it should be fine. The volume can be calculated by using the following formula: height x depth x width.

Step 3: Cut the wood

After completing calculations, you can start cutting the wood into the pieces you will later glue and screw together. Measure the woofer diameter and cut the hole in the speaker’s front panel. You should also drill a hole in the back panel because you will need to put some wires through it to connect the speaker to the power supply. You can reinforce every corner of the wood parts because it will make the box sturdier and more resistant, especially at high volumes.

Step 4: Put the pieces together

The next step is to put all the parts together but before that, it would be great to smooth the rough edges because every deviation can affect the performance. After that, you can take the glue/adhesive/caulk and start gluing the pieces together. It is very important to leave the adhesive to dry completely at least for 24h.

You might also want to put a layer or two of insulation (fiberglass or something similar) to smooth the speaker box walls so that the air can travel smoothly in and out of the box without affecting the overall performance.

Step 5: Customize your speaker box

Don’t leave the box like this. Apart from being stable and durable, it should also look nice so it would be good to paint it. If you are really in the mood, you can also think about buying some cloth or carpet that you can use to cover the speaker box surface. In order to do that, you will also need some calculations, a marker, and a scalpel but this is the topic for some other article.