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H
W
D
5
Enclosures
between the various enclosures.
Building an Enclosure
To work properly, the walls of the enclosure must be rigid and not
flex when subjected to the high pressures 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 and secured with nails or screws.
Calculating Volume
Calculating volume is merely a matter of measuring the dimensions
in inches and using the formula: H x W x D divided by 1728 (cubic
feet). See block below.
Box Volume Height” x Width” x
Depth”
Divided by (cubic
feet)
1728
If two facing sides are of uneven length, add them together and
divide by two 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 speaker
itself also reduces the internal volume. The amount of air displaced
by each model is listed on the specification sheet and should also be
subtracted from the gross volume calculation.
Sealed Enclosure
NOTE: Vb is the internal volume, before any speaker and/or port
displacement is added. All external dimensions were based on
the use of 3/4” (1.90cm) materials.
NOTE:
When using enclosures other than recommended, call
Technical Support for correct application.
Optimum Sealed Enclosure Recommendation
Sealed Enclosures 8” 10” 12”
Total Internal Volume cu. ft.
(Liter)
0.55
(15.62)
1.1 (31.15) 1.65
(46.72)
Woofer Displacement cu. ft. (Liter) 0.05(1.41) 0.1 (2.83) 0.12 (3.4)
V
b
- Net Internal Volume cu. ft.
(Liter)
0.50 (14.2) 1.0 (28.32) 1.53 (43.32)
F
3
- 3dB Point (Hz) 47.7 58.4 43.1
Qtc - Enclosure Damping 1.19 0.66 0.88
H - Height - inch (cm) 12 (30.48) 14.0 (35.56) 15.0 (38.1)
Carton Contents
• (1) Element Ready ™
Subwoofer with fixed Sport
Grill
• (6) Socket Head Stainless
Screws
• (1) COLOR OPTIX™ Harness • (1) 1/8” Drill Bit
• (1) Socket head driver bit • Installation and Operation
Manual
Recommended Enclosures
This manual outlines two specific types of enclosures that provide
distinctly different performance. This section is to help you decide
which type is best for your application.
Sealed Enclosures
Sealed enclosures are the simplest to build. The most important part
of building a sealed enclosure is to make sure that the enclosure is
airtight. Using glue and some type of sealant on all seams will ensure
solid construction and prevent air leaks. The box volume will directly
impact the performance of the speaker. Larger enclosures will
provide flatter response and deeper bass where smaller boxes will
provide a bump in the response curve and generally higher output
for greater SPL.
Advantages of sealed enclosures:
• Small enclosures
• Linear (Flat) response
• No port noise
• High power handling at all frequencies
• Excellent for sound quality
• Extended low frequency output when compared to vented
enclosures
Vented Enclosures
Vented enclosures vary only from the sealed enclosure in that a vent or
port is added to “tune” the enclosure. The enclosures recommended
are designed for great overall performance. Larger boxes tend to be
easy to tune to lower frequencies while medium and small boxes are
easier to tune to higher frequencies. The vented design is less linear
in response than the sealed box but with noticeably more output at
the tuning frequency.
Advantages of vented enclosures:
• Higher average output than sealed
• Tuning frequency can be easily adjusted by changing port length
• Deep bass response with lower power requirements
• Great for high output with limited power
Infinite Baffle Design
These designs typically called “IB”, are the easiest enclosure types to
build. The reason is that you are not actually building an enclosure,
but rather simulating one. This is done by closing off a cavity area
(ie; car trunk, enclosed area of a boat hull) with a baffle board. This
creates your “IB” sub-woofer system. Essentially, an “IB” design can
just be considered a large sealed enclosure design. Given that an
“IB” design does not rely on a volume of air for its suspension, the
low frequency output is driven by the speaker’s inherent damping
or “Qtc”.
Advantages of infinite baffle design:
• Easy to build
• Light-weight
• Deep bass response with lower power requirements
Vented vs Sealed vs Infinite Baffle
The graph shown here is a sample of how SPL and Excursion differs