Polk Audio EX Series II Subwoofer EX652a - Manual (Page 5)

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PARTS YOU WILL NEED TO BUILD YOUR ENCLOSURE
There are three choices of enclosure material:
1. Particle board
2. Medium density fiberboard (MDF)
3. Marine grade plywood
These materials range in price as well as availability. Particle board is the most common,
least costly, and can be purchased at most hardware stores. MDF and marine grade plywood,
although preferable, are usually much harder to find, and more costly. Whichever you
choose, we recommend that its thickness be 3/4". This will provide the rigidity necessary for
optimum performance.
If you have never built an enclosure before, we are going to try to make this as easy and
painless as possible. If you have built enclosures before, you can skip this section and go
right to the specification page to get the technical parameters.
1. Wood (particle board, MDF, or marine grade plywood ) 4' x 8' x 3/4" sheet
2. Wood glue (one bottle)
3. 1 1/4"x #8 wood screws (one box)
4. Caulking gun and silicon caulk (two tubes)
5. Terminal cup (one per speaker) available at electronic parts stores
6. Speaker wire
7. Carpet (optional)
8. Grilles to protect your subwoofers (optional)
9. Solderless speaker connectors (available at electronic parts stores)
Second, designing band-pass boxes is as much art as science, just because a computer
program says that a certain design will work is no guarantee that you will like the
performance of the finished design. Third, all subwoofer enclosures exhibit a phenomenon
known as “group delay”. It means that the sounds from the subwoofer will lag in time from
the sounds created by your high frequency speakers. This causes a smearing of the sound
and in worst cases a ping-pong effect from the highs in the front of your car to the bass in
the rear. Band-pass boxes are especially prone to long group delays. Finally, the pressures
and vacuums formed within a band-pass box can be extremely high, if the subwoofer you
are utilizing does not have a very stiff cone. It can buckle under the high pressures, making
very bad noises. The Polk EX subwoofers utilize 1mm thick mineral filled cones, and are
extremely well suited for use in band-pass enclosures.
TOOLS YOU WILL NEED TO BUILD YOUR ENCLOSURE
If you have decided to build your own enclosure for your Polk EX subwoofers, here is a list
of the tools you should have available.
• Calculator
• Assorted drill bits
• Screwdriver bit for drill or manual screwdriver
• Circular saw
• Tape measure
• Drill - electric or cordless
• Jig saw