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EXPLANATION OF ENCLOSURE SPECIFICATIONS
There are many different factors that help determine the best style of enclosure for
you or your vehicle. Listed below are some factors that should be considered.
The size of the enclosure is directly proportional to the efficiency and power handling
of that speaker. A woofer in a smaller enclosure will handle more power than the
same woofer in a larger enclosure. The exact opposite is true for efficiency, a larger
enclosure will play lower frequencies at a higher volume with less power than a
smaller enclosure.
The sealed enclosure design following is best for overall sound quality. The enclosure
size to use will depend on the power and type of vehicle that it will be placed in.
Larger enclosures are best suited if you have smaller amounts of power (25% to 50%
of speaker’s power handling), have a larger vehicle or looking for greater output. A
smaller enclosure should be utilized if you have recommended power (50% to 100%
of speaker’s rated power handling), have a smaller (high gain) vehicle or are looking
for more accurate sound reproduction. The smaller sealed enclosure will yield more
control, this audible translates into faster and more accurate bass.
A vented enclosure will offer greater efficiency and stronger low bass output
compared to a sealed design. A vented enclosure uses the back wave (sound from the
back side of the cone) to reinforce the output from the speaker. A properly tuned
enclosure will yield gain across the entire bandwidth of the subwoofer system and
offer more cone control than a sealed enclosure. A low tuning will yield less overall
gain but greater extension (low bass). A high tuned enclosure will offer more gain but
limit the low end response of the system. One of the advantages of having a vented
enclosure is because it is tunable to a specific frequency and that tuning frequency is
known as the “Fb”. Another important box specification is “F3”, which is the rolloff
frequency at which the driver’s response is down 3dB. This is an important number
when it comes to setting your a highpass filter or your ORION IntelliQ. The IntelliQ
should be set at the same frequency as the “F3”as this will keep the speaker from
damaging or what is know as overloading.
Good planning and proper construction will assure the best response from your
system. The next pages will outline many different enclosures and designs that allow
the HCCA subwoofers to perform best. As always, if you have any questions on
enclosure construction or design, call Technical Support 1-800-753-0800.