Building an Enclosure
To work properly, the walls of the enclosure must be rigid and not
flex when subjected to high pressure generated by the speaker's
operation. For optimum performance, we recommend using 3/4" MDF
(Medium Density Fiberboard) and internal bracing. The enclosure
should be glued together along with support of screws or nails.
Because MDF is porous, it is suggested that you seal the outside with
polyurethane prior to painting or carpeting.
Calculating Volume
Calculating is merely a matterof measuring the dimensions in inches,
and using the following formula:
Box Volume = (Height) x (Width) x (Depth) divided by 1728. This will give
you the volume of the box in cubic feet.
If two facing sides are uneven length, add them together, and divide
by 2 to take the average. Using this number will give you the volume
without the necessity of calculating the box in sections, and adding
the sections together. The thickness of the baffle material reduces
the internal volume so this must be subtracted from the outside
dimensions to determine the internal volume. The amount of air
displaced by each model is listed on the specifications sheet in this
manual and should also be subtracted from the gross volume
calculation. All box parameters include displacement for ports and
subs. These specs do not include the volume of the material used to
build the box, so this must still be factored into the calculation.
Subwoofer
There are two operational types of crossovers, passive and active.
Passive crossovers (coils and conductors) are placed on the speaker
leads between the amplifier and the speaker. An active crossover is an
electronic filter which separatesthe audio signal fed to different
amplifiers. For optimum subwoofer performance, we recommend using an
active 80-100Hz low pass crossover at 12dB/octive.