January 5, 2022

Lil Thumper build

First the internal baffles are glued together and Tnuts are tapped into place. 

It's a good idea to seal the internals before assembly. Later, it will be difficult to access. Here I'm using Duratex rolled on. A heat gun speeds up the process so that we can move on quickly. 

Now the back and braces are laid out. You can see the braces sit into machined trenches.

 These braces are laid down first. 

The next bracing pieces lock into the others. When combined with the trenches on the back panel, this ensures all the braces are located in the correct positions. No guess work involved.

 Braces are now secured to the back panel.

Lining is glued in place. Here I'm using high density panels that we also use in bass traps. Normal speaker box lining is not quite so effective at damping port resonances. I've found that thicker and higher density material works much better and ensures the output is clean.

 The baffle is laid out and now glue is applied.
Lowering the internal baffles into place.

The first side panel is glued into position.

The second side is glued into place.

Now with the second side in place, the clamps are moved.
Solid timber braces put into place. These will be glued in place later. The absorber panels are already glued in place. Later, access is impossible. The unpainted parts are the trenches on the sides, top and bottom.

Top panel clamped into place.
This is a dry fit to show the internal structure.
I haven't taken photos of the assembly of the solid timber braces and the port, which has four pieces, with round overs on both inlet and outlet. There is also a brace not shown. This part of the build was fairly involved, with many panels being secured in rapid succession. It's difficult to handle the camera when dealing with polyurethane glue. 

Now with all panels in place, clamps are re-positioned. The timber here allows less clamps to be used, applying the force over a larger area. Otherwise, more clamps with small spacings are required.
This is the rear of the sub. A circular cut out allows the driver to be inserted into the internal baffle. The amp is then installed to a panel that goes over the top.

The enclosure is left over night, then the next day, sanded and a small roundover is applied to all the joints.

Next the driver can be installed. I like to insert string through the holes so the driver can be re-positioned. Otherwise the driver might not be rotated correctly and the pilot holes might not line up.

The driver is lowered into the internal baffle. Cables are routed to avoid hitting the cone. Foam gasket avoids air leaks.

Next the back panel is added and the sub is tested.

It's not pretty, however, this sub is now located behind a large couch and can't be seen in the room.

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