Introduction: How to Build a Loudspeaker
Building a loudspeaker kit
we have designed a loudspeaker kit which we think is pretty good. We have made it as easy as possible to build, and we think you will agree.
The sound is good and it is great value. The kit is available with a box similar to the one in the pictures, or you can just buy the components and build a box yourself. This is only one solution. If you would like to purchase it here is a link paradoxloudspeakers.com.au and there is more info there. Click on the images on the home page. The 10 inch subwoofer should be out before the end of February. Click on it for some of the design goals.
Step 1: Items and Tools You Will Need
Some of the tools you will find useful are:
a. PVA glue that dries clear, because it is easier to clean up;
b. A holt melt glue gun;
c. Super glue;
d. Two part epoxy;
e. Glue applicators. We used cotton buds;
f. Masking tape 50mm wide green or blue;
g. Packing tape 50mm wide;
h. 3 mm Allen key or suitable driver;
j. A soldering iron;
k. Some tinned copper wire;
l. Side cutters;
m. A drill;
n. Paper towel or rags.
Step 2: Assemble the Crossovers
We discovered that it is a good idea to assemble the crossovers and screw them to a panel, because the box is relatively small. If you try to install the crossovers after the box is assembled you will struggle to fit it in and screw it down.
So start by assembling the crossover.
Solder the leads, and label them according to the plans.
Get one of the small panels out, Work out which is the inside of the box and the outside. Drill holes in the panel using the holes in the crossover board as a template on the inside of the panel, but don't screw it down yet.
Step 3: Fit the Port to the Rear Panel
Test fit the PVC port into the holes on the rear panel. If it is tight, a little superglue will hold it. If it is a looser fit you may prefer a two part epoxy such as Araldite, which fills gaps better. If it falls out it will be difficult to put back in so use the appropriate glue. Usual words of caution using super glue inserted here.
Step 4: Lay Out the Panels
Lay out the panels in the right order, top, side, bottom, other side, with the mitres to the bottom.
The mitred edges should be aligned as straight as possible and facing downwards. You can use another panel, and push them against it to align them.
Step 5: Apply Masking Tape
The masking tape acts as a clamp.
Put tape on each joint, and then across all the panels.
If it does not feel tight enough, you can put packing tape over the masking tape, but don't put it directly on the box, because it might leave a trace behind.
Turn your panels over, carefully.
Step 6: Test Your Fit
Now is the time to test everything lines up. Don't put any glue down yet.
If you put the panels in the wrong order it will show up.
If all the panels line up, and the fit is tight screw you crossover down where you drilled the holes.
If the fit is not tight, you can add packing tape over the top of the masking tape, stretching it slightly. Don't stick packing tape to the timber, because it may leave a residue.
If it does not line up, undo the tape and align things again, then screw your crossover in.
Step 7: Glue the Box Together
Apply glue to the joints, spread around using your applicators, or fingers.
PVA is very safe, but you have to be careful not to get it everywhere, which is why we recommend using applicators.
The rear panel will fit in a rebate in the four panels you have taped up.
You should put glue in the rebate, and put the rear panel in as you fold up the box. The large hole in the rear panel goes towards the bottom of the loudspeaker.
Step 8: Glue the Box Together
Once you have applied the PVA glue, fold it up again.
Pay attention to alignment, and stick down the tape nice and tight.
Step 9: Glue the Front Panel On
The front panel, usually called the baffle, is glued on next.
Apply the glue, carefully place the panel on. Apply masking tape to hold it down.
Make sure it is centred. Wipe any extra glue off.
Step 10: Solder the Speaker Terminals
Solder the speaker terminals, and then screw them into place.
Step 11: Install the Speaker Drivers
Solder the tweeter, and screw into place.
You should use a 3 mm Allen key, but if you are very careful a drill set at the lowest torque setting can be used.
Once done, solder the woofer, and screw in.
You can use spade connectors and crimp them, instead of solder if you prefer.
Connect your speakers up to your amplifier, call up some music and enjoy.