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actual air space available. The following worksheet has been designed
to provide you with the necessary steps to accurately calculate the
absolute (Net) internal volume of any given enclosure.
Measure maximum possible dimensions
Multiply wall thickness by 2
Subtract this from each dimension to
arrive at Gross internal Dimensions
Multiply LxWxD to arrive at
Gross Internal Volume
Deduct Vf (volume of the speaker frame)
from Gross Internal Volume
Calculate brace volume and deduct
from Gross Internal Volume
V
You are at Net Internal Volume.
in cubic inches (if?)
Calculating Cylindrical Port Volume
1. Measure the outside diameter of the
port and divide by 2 for the radius.
2. Square the radius and multiply by
3.14 (71) to arrive at outside port area.
3. Multiply the area by the length of the
port inside
enclosure for the port
the
volume.
70 CORYMf ro LITERS:
Divide ins by 61.03
Divide ins by 1726
0
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Determine the dimensions of your enclosure.
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Sometimes making a cardboard box with the same outside
chosen.
dimensions is helpful.
Use 3/4 inch thick Medium Density Fiberboard (MDF) or High Density
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Particleboard. It is preferable to cut the wood with a table saw to ensure
straight, even joints. If a table saw is not available, a circular saw is
acceptable.
Use a "T" square to verify precise right angle gluing.
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Use a high quality wood glue and air nails or wood screws to assemble the
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enclosure. Elmer's@ woodworker's glue and Weldwood@ work well. To
guarantee an airtight box, seal each inside joint with RTV silicone glue.
For Sealed Enclosures, stuff the chamber with 50-75% filling (approximately
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1.5 pounds per cubic foot) of fiberglass insulation or Dacron.
For Vented Enclosures, staple 1 inch thick fiberglass insulation or Dacron to
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all walls of the enclosure except the baffle to which the woofer is mounted.
Use the supplied gasket to seal the woofer in the enclosure and eight(8) wood
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screws or T-nuts and bolts. Progressively tighten each of the bolts or screws
to prevent warping the woofer frame.
Use slide-on connectors to attach speaker wires. Do not solder wires to the
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provided terminals as this may cause damage to the factory wire connection.
This may also void the speakers warranty.
SUGGESTED ENCLOSURES
The following designs include a variety of enclosure types. Each
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design has a frequency response curve that shows predicted output
with 2.0 volts input, measured at 1 meter. 2.0 volts across a 4R load
corresponds to 1 watt per speaker. Also, each frequency response
curve was generated using a 12 dB/octave low pass filter at 100 Hz.
The performance of each of these enclosures will be different once
installed in a car. The amount each enclosure will vary depends on the
car and installation location. The "standard" curves given correspond
to performance outside the car to help you visualize relative
performance differences. Read through the descriptions given for
each enclosure and select the one that suits your needs.
Remember: all suggested enclosure volumes are Net, and DO NOT
include woofer, port, and bracing displacement!
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