The Construction
All comments are associated with the picture below them.
All measurements are in "mm" and are approximate. I will do my best to cross check and sanity check the stack up, but there may be some minor variations. Width is from side to side in the cabinet, Depth is from front to back of the cabinet and Height is up and down in the cabinet... ALWAYS!
This is a KEF R107 Cabinet with the "Top Hat". The cabinet itself measures
330W X 450D x 790H. The Top Hat is about
350H.
So let's talk about the outer cabinet construction. The cabinets are made out of
23mm thick MDF and finished with a Walnut Veneer (Black Ash and Rosewood were an option). The front joint construction has a
10mm quarter round in the corner with a fairly complex joint behind them. The backs appear to be a mitre joint.
I believe everything is glued and tacked prior to the veneer being applied, but what is interesting is the veneer is wrapped up onto the ends of the cabinet sides. So perhaps the cabinet sides are pre-veneered, machined and then assembled. That doesn't make sense to me, but the pictures don't lie. There are four cabinet divisions that span from the top to bottom of the cabinet and again, I would think they would be tacked in from
the outside prior to the veneer being applied. We'll discuss these partitions in more detail later.
In talking about the complexity of this cabinet design it is probably best to start at the bottom. This image shows the base of the cabinet.
The Base Cover is made out of
23mm thick MDF and protrudes from the bottom by about
5mm. The outside external edge has about a
5mm bevel for esthetics. It is held in place by 10 screws that screw into pressed in threaded fasterners attached to the
Base Plate. The Base Cover measures
405D X 285W X 23T.
The fasteners in the corners of the backside of the Base Cover (same type as are in the Base Plate) are used to attach the feet. Also note that there is a relief all around the outside for a gasket! The depth of the relief is less than the gasket thickness to create an air tight seal.
This image shows the
Base Plate which is the lowest of the four divisions within the cabinet. This is used to support the mounting of the Base Cover. This is made out of
18mm thick MDF, which all of the dividers are. So this would be
285W X 405D X 18T. The inner opening in it is
245W X 365D (ie; the web is 20mm thick) with a
25mm Radius on the inner corner.
This is inset into the cabinet by
18mm, so when the
23mm cover is mounted, as I pointed out before, it protudes by about
5mm. Also note the reliefs for the threaded fasteners for the feet.
The mounting holes are
130mm on center in X&Y. On the X axis the first hole starts
70mm across from the inside edge. In the Y axis the first hole is at
80mm up from the inside edge.
OK, let's talk about foam. The KEF R107, being the speaker it is, has some pretty sophisticated dampening placed inside the cabinets. And you can rest assured a lot of development went into where the foam is placed and why. It is a standard open cell form of foam
kind of like these, but it is placed and cut with some precision and care.
The picture below shows the foam that has been cut right to the opening in the Base Plate (notice the black pen outline). It measures
250W X 390D X 50T. The base plate is 18mm thick, so this piece sticks down into the cavity and is meant to compress a bit.
Removing this reveals a less densely blown foam that fits to the measurements of the inside of the cabinet. So it is about
285W X 405D X 100T.
This image shows the difference between the densities of foam and the sizes.
Looking inside the lower bass cavity, there is foam that has been placed around the speaker to give it room to extend and generate sound. This
Foam Pocket is created by a strip of
25mm thick and 45mm height foam that extends
280mm into the enclosure from the back panel. In other words, the strip is probably
~850mm Long but spans an area
285mm wide (width of the internal cabinet space) and
280mm deep (from the rear panel to where it interfaces with the foam block), and again is
25mm thick all around at a height of 45mm.
It is important to note that this
"lower bass cavity" (285W X 405D X 190H) is fully enclosed and does not vent. The rectangular piece of foam that creates the support along with the strip described above is
285W X 125D X 45T.
The opening for the speaker is a hole
240mm Diameter that is centered across the width and
20mm in from the rear panel of the speaker. As mentioned above, all dividing panels are
18mm thick.