Introduction: DIY Speaker Guide
In this guide, I will go through the process of building your own set of speakers.
It is important, that you read the entire guide before you start to build your speaker
to make sure you can complete all the steps. If you are unfamiliar or don`t know how speakers work I would suggest reading this article: http://www.ht-audio.com/pages/SpeakerBasics.html
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Step 1: Getting All the Components
Before you can build the speaker, you need to make sure that
you have all the components. You could either pick out the parts yourself or buy a kit. The kit should include all the part needed to build the speaker, but I would still advise reading the guide.
Step 1.1: Deciding on the type of speaker
Before looking for the speaker components, you first need to decide on the type of speaker you want. There are 3 main types of speakers, Three-way, Two-way and Full range speakers. The Three-way speaker is the largest of the speakers. It features 3 drivers. A tweeter, midrange, and a woofer. These speakers can normally cover the entire frequency spectrum, that a human can hear(20Hz-20kHz). The Two-way speakers have two drivers, one tweeter, and one midbass/woofer. They are typically smaller than a Three-way speaker. Most of the bookshelf speakers can cover the whole frequency spectrum, except the very the low frequencies. They can be paired with a subwoofer to achieve a similar sound as the Three-ways. Full range speakers can be the smallest of all the speakers and they only have one driver. While these can cover most of the frequency spectrum, they lack high and low end. Of course, each type of speaker can vary in its size. This means that there could be two-way speakers that are bigger than a three-way speaker.
Another thing to consider is whether you want to have a vented/ported or sealed speaker. A vented/ported speaker has a port in the speaker cabinet. The port increases the low-end performance of the speaker while increasing the size of the cabinet.
Step 1.2: Picking out drivers
Once you have decided on the type of speaker you want to build you need to select the drivers. You can buy the parts in a local audio store or online. Some of the rather larger sites are https://www.madisoundspeakerstore.com/ and https://www.madisoundspeakerstore.com/ . When picking out components there are a few factors you need to keep in mind: Power handling (RMS), Sensitivity, Size, Price, Sealed/Vented Volume and Frequency range. Power handling and Sensitivity are responsible for the loudness of the speaker (dB). The sensitivity is the loudness at 1 watt. The power handling (RMS) is the power the driver can handle. The power increases the volume of the speaker on top of its sensitivity. Each time the power is doubled there is 3db volume gain. Here is an example, with a driver that has a sensitivity of 90dB:
1 watt = 90dB + 0db
2 watt = 90db + 3db
4 watt = 90db + 6db
8 watt = 90db + 9db
16 watt = 90db + 12db
To find out if the component is loud enough for you, you can calculate the volume on this website: http://myhometheater.homestead.com/splcalculator.... .
If you’re a building a two or three-way speaker it is important, that the driver has overlapping frequency responses. If they don`t have overlapping frequency responses, they can`t cover the whole frequency spectrum.
The size of the driver and the Sealed/Vented Volume determine how big your speaker is going to be. The Sealed/Vented Volume state at what cabinet volumes the speaker perform best.
If you buy the drivers it is always a good idea to read some reviews or ask someone about the speakers. They often include tips on how to use the driver to get the best possible sound.
Step 1.3: Picking out crossover partsIf you are building a
speaker with more than one driver you must use a crossover to split the signals between the drivers. The crossover is made out of capacitors, inductors, and resistors. Firstly, you need to pick the type of crossover you want. There are 4 main types. A first order, second order, third order and fourth order. The order of the crossover tells you how many components there are for each driver. Each component reduces the signal after the crossover point by 6db per octave.
Another thing to note is that each component introduces a 45 degrees’ phase shift. This means if you have a two-way speaker, with a first order crossover the drivers will each have a 45 degrees’ phase shift in different directions. This means the speaker will have a 90 degrees’ phase difference between drivers. When using a second order crossover, each driver has a 90 degrees’ phase shift. You can then reverse the polarity of the tweeter, which creates an 180 degrees’ phase shift. The tweeter then has a 270 degrees’ phase shift, which means it has the same phase shift as the woofer. This means there is no phase difference between the drivers. A fourth order crossover creates an 180 degrees phase shift for each driver. There is no need to reverse polarity since the drivers are already in phase. I recommend either having a second or a fourth order crossover. You can calculate which crossover parts you need on this site: http://www.erseaudio.com/CrossoverCalculators
Another thing you will need is an L-pad Attenuation. This will decrease the sensitivity of your driver. This is useful if your drivers don`t have the same sensitivity.
Additionally, you need to get a Zobel circuit for all the woofers. The Zobel circuit will help the crossover function properly.
Take screenshots of all your calculations and the schematics, as you will need them later.
When you can`t find the parts with the same value as you calculated pick out the ones, that have the closest value.
Step 1.4: Picking out the rest
This is a list of additional things that you will need for your speaker.
· Binding Post/Terminal cups
· Case/Cabinet feet
· Dampening material (Either foam or stuffing)
· Amplifier (External or Internal)
· Mounting hardware (screws)
· Speaker wire
· Flared port (To calculate the length follow this guide: http://www.mobileinformationlabs.com/HowTo-1Woofe... )
· Passive radiators (An alternative to ports. The radiator (1 or more) must in total have double the surface area of the woofer.)
· Speaker grills
· Banana plugs (if needed for Binding Post/Terminal cups)
· Solderless / Crimp Terminals (Buy them in a few different sizes if you`re not sure which you need)
Step 1.5: Buying
Before buying the parts carefully check that all the parts are correct and that they work with each other. Redo all the crossover calculations and check if you have the right components. After that, you should be ready to buy all the parts. If you know any experienced speaker builders ask them to look at your shopping list. If you are uncertain you could also ask people on online forums.
Step 2: Step 2: Testing the Parts
Open all the boxes and check for any physical damage.
Turn the volume of your amplifier down and connect one driver at the time. Then play some music to make sure they sound alright. If you turn up the volume too high you risk breaking them.
If not all the drivers function properly I suggest contacting the seller.
Step 3: Making the Crossover
Tools: Hot glue gun, soldering kit, wire cutter/scissors
Step 3.1: Getting the schematics
You should have already made screen shots of the schematics, if you didn`t you must go back to step 1.3 and redo the calculations
Step 3.2: Planning the crossover
Once you got all the parts you need to test assemble them. Most of the crossover will have an L-pad and a Zobel circuit. The order on how to assemble theses is:
Amplifier à CrossoveràL-padàZobel circuitàDriver
You can just leave out the sections, that you don`t need.
You can lay out all the parts on the floor and then compare them with the schematics.
Step 3.3: Gluing the crossover
If you feel like you assembled the crossover correctly, you can glue them onto a piece of MDF. You need to make sure that the piece of MDF will be able to fit into your cabinets. I suggest gluing the components on with a hot glue gun.
Step 3.4: Soldering
Once all the components are glued to the board you can start soldering.
If you don`t know how to solder I recommend reading this guide:
Step 3.5: Testing
Once the crossover is complete you need to test it. This should be done in the same way as you have done the testing in step 2.2. The only difference is that in-between the driver and the amplifier you have the crossover.
Step 4: Building the Speaker Cabinet
Step 4.1: Getting all the tools
To build your own speaker you will need a couple of tools.
· Drill with adjustable circle cutter (wood)( Can only be used with round drivers, that don`t exceed the size of the hole cutter) or a Jigsaw
· Wood glue
If you don`t own some of the tools, I would suggest asking a friend if you can borrow some tools, since some of the tools are rather expensive. Another option is to go to a workshop and to pay someone to do it.
Step 4.2: Planning the cabinet
Before buying the wood you first need to plan your speaker. The first thing you need to know is the internal volume of your speaker. If you have more than one woofer/non-closed midrange you need to have two separated spaces in your cabinet. It can be found on the spec list of your woofer. It is called sealed/vented volume depending on whether you have decided to have a ported speaker. When you have that value, you need to calculate the cube root of the volume. This how long each site needs to if you want your speaker to look like a cube. If you want, your speaker to have the more of a traditional speaker design I would suggest doing the following calculations.
L= cubic root of the volume
Depth: L X 1
Width: L X 0.618
Height: L X 1.618
These values can be slightly adjusted as long as the volume stays the same.
Once you have these values you need to plan the pieces of wood you will need. You will need to make some of the wood pieces bigger to accommodate for the thickness of the wood. You also need to make sure that you driver can fit in the cabinets.
Another thing you will need is bracing. This is needed for drivers with a lot of low end. This a piece of MDF that supports the speaker integrity.
Step: 4.3: Buying the wood
The recommended wood for building speakers is MDF. You can use hardwood if you want, although a lot of experienced speaker builder claim that cabinets made out of MDF have the best sound. I recommend having 10mm thick wood for medium sized bookshelf speakers. For subwoofers, you will need at least 20mm thick wood. I recommend going to a local wood seller and asking them to cut the panels out for you. Otherwise, you will need to do that yourself.
Step 4.4: Sawing the holes for the drivers
Before you start cutting the holes, you need to draw them on the wood. You can find out the size of the hole by looking on the spec list for cut out hole size. If you can`t find the size on the spec list you can measure it yourself. If you are using a drill with adjustable circle cutter you need to adjust the circle cutter to the right size. Then you need to attach the wood to a table edge with a g-clamp. It`s important that the part of the wood in which you are going to cut hole is placed off the table edge, to make sure you are not cutting into the table. After cutting the hole you must sand them.
Step 4.5: Gluing the cabinet
To glue the speakers, you need to apply the glue on the joints. Once you have assembled the speaker with all the joints glued together, you attach F-clamps to it. Make sure the clamps are very tight. You should then let the cabinet dry for about 24h.
Step 5: Assembly
Step 5.1: Assembling.
You can now assemble the speaker. Make sure that all the parts can still be removed afterward. Firstly, you glue in the crossover. Then you connect the crossover to the binding ports and you then attach the binding ports to the cabinet. The next thing to attach is the port if you have one. After that you fill the cabinet with the acoustic stuffing or you glue on the dampening material, depending on what you have. Then you attach the drivers and passive radiators. If you screw anything into the wood I recommend first drilling a small hole into the cabinet before screwing in the screws. An electric screwdriver can make screwing in the screws a lot easier.
Step 5.2: Testing
Once the speaker is assembled, you can hook it up to the amplifier to test it.
Step 6: Decorating the Cabinet
You can now decorate the
cabinet. Before you start decorating I would suggest disassembling the speaker again. There are many ways to decorate speakers. This is a list of examples that I came up with:
· Spray paint
· Wood veneer
Step 7: Finishing
Step 7. 1 : Final assembly
You can now assemble the speaker for the last time. This should the same way as in step 4.6, except that you can now attach the part permanent.
Step 7.2: Enjoy
Set up your speakers, put on your favorite song and enjoy.
"Speaker." pinterest, s-media-cache-ak0.pinimg.com/736x/1d/6e/b5/ 1d6eb5a444f6958e3d6b8b47b35a8d23.jpg. Accessed 5 Jan. 2017. "Speaker2." innovatecar, innovatecar.com/wp-content/uploads/2016/07/ Difference-between-Two-way-and-Three-way-Speaker.png. Accessed 1 Jan. 2017.