So, the WiBAQ. The official WiBAQ thread is here
. But the original inspiration is in a different thread, linked to on the WiBAQ thread. The speaker utilizes a Wild Burro Audio Labs Betsy K full range driver, which is available through Wild Burro Audio
for 110 dollars a pair. For their performance, these drivers are some of the best value on the market. The driver is mounted in a mass loaded transmission line enclosure. This means that the port at the bottom adds resistance to the air moving in and out of the cabinet, which is being pushed/pulled by the driver. This effectively increases the size of the cabinet. This is similar to how a standard ported speaker works. But in a transmission line, the length of the "line" or "pipe" behind the speaker is one quarter of the tuning frequency. Here, the mass loading of the port and height of the speaker together tune the enclosure to 35 Hz. This gives the enclosure an f3, (or a 3db cut off, or the point where the volume at that frequency has decreased just enough to be noticable) of 35 Hz, which is actually pretty low, especially with a speaker of this design.
Pictured is a Google Sketchup model of the speaker. The dimensions given are the inside dimensions. Its the insides that are the important ones, since its the inside ones that dictate the tuning of the enclosure. The external cutting dimensions of the enclosure will be given later in the Instructable.
The first PDF is the original design with the driver mounted 15" from the closed end. This was later changed to 9" from the closed end and the new frequency response chart included in the second PDF. All the information in the first PDF still applies when the driver is 9" from the top except for the frequency response. In these PDFs you can see the ruler flat bass response, with no peaks or humps, as well as the high 95db sensitivity