Specifications

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Car Audio Reference Guide
Subwoofer Enclosure Guide
Even the most expensive, complex subwoofer on
the planet won’t sound good unless it is installed
in a properly designed and constructed enclo-
sure. The following section outlines subwoofer
enclosure design and construction guidelines.
Construction Notes
All enclosure should be constructed of 3/4” thick-
ness North American-produced MDF or high-
quality plywood with one finished side (installed
facing the inside of the enclosure). The use of
particle board will result in substandard perform-
ance and could potentially lead to premature
speaker failure.
• All enclosure joints must be secured with
screws or nails.
• Wood glue (or equivalent) must be used along
the edges of all joints.
• All panel joints should be sealed with appropri-
ate caulking material - latex or rope caulk. Do not
use Silicone sealant - the gases that are released
during the curing process may be harmful to the
adhesives used to assemble a subwoofer.
• Large panels should be reinforced with an
internal brace to reduce panel flexing due to the
pressures created inside the speaker cabinet.
Likewise, around the mounting face of the sub-
woofer, braces should run from the front panel
to the rear panel of the enclosure to further
strengthen it.
• Clarion does not recommend the use of passive
crossover components with our subwoofers
(Inductors or Chokes). We recommend that a
dedicated subwoofer amplifier with an integrated
electronic crossover be used to achieve maximum
performance from the sub-bass system.
• Where applicable, Clarion recommends the use
of a subsonic filter in ported enclosure applica-
tions.
When calculating enclosure volumes, please
remember to include the volume of the sub-
woofer, the vent(s) and/or brace(s) in your calcu-
lations.
• For optimal performance from your subwoofer
enclosure, the ideal ratio of Width to Height to
Depth should ideally match the Greek Golden
Rectangle ratio of W=1.0, D=0.618 and H=1.618.
This ratio of dimensions results in a reduction of
standing waves inside the enclosure and the best
possible sonic performance.
• Where applicable, the inside and outside edge
of all vents should be rounded over (radiussed)
to smooth airflow over the edge of the vent. This
can be done with a router and a round-over bit.
The use of Aeroports (or equivalent) also work
very well.
Subwoofer Enclosure Application Chart
There are many different styles of subwoofer
enclosures - sealed, vented, bandpass, transmis-
sion line, aperiodic, isobaric and multi-chamber
vented - just to name a few.
Each enclosure has different strengths,
characteristics and weaknesses. The chart below
provides a generalised overview of the differences
between some of the most common enclosures.
Clarion recommends the use of Sealed (Acoustic
Suspension) or Vented (Bass Reflex) enclosure
for our subwoofers. These enclosures are the
easiest to design, offers the best dynamic and
transient response characteristics and is the
most tolerance of design and construction errors
- bottom line, they always sound great!