I T
SERIES
SUBWOOFERS
Applications
The Cerwin-Vega IT Series subwoofers are specifically
designed to be used in small sealed enclosures for optimum
performance with long-term reliability. Thevery low resonance
frequency of each IT subwoofer results in tight, well-controlled bass
where space is limited.
Caution: By definition subwoofers with a low resonantfrequency
designed for small sealed enclosures have a very compliant (soft)
mechanical suspension system. Consequently, high power
application ijz enclosures which are larger than the recommended
volume could result in mechanical damage to the woofer.
For best results, at minimum we recommend lining all inside
box walls with acoustic fiberglass or DacronT” fiberfill of one-inch
thickness. By loosely filling the enclosure (see figures in “enclosure
recommendations”) the enclosure with acoustic fiberglass or
DacronTM fiberfill, the enclosure volume may be reduced by lo-15943
yielding the same results. It is ZW~J importrrvzf that the box have no air
leaks. The more rigid and well-sealed the enclosure, the more
accurate and controlled the bass response. Remember that with small
sealed enclosures, dimension tolerances are highly critical. Please
pay particular attention
that
internal box dimensions match those
recommended in this manual.
The final box shape should be determined by individual space
considerations. Although the shape of the box is not critical to
performance, the length, width, and depth of the box should all be
different dimensions. This prevents common mode resonance that
can occur in the walls of the enclosure. Optimum performance is
achieved when the ratio of the wall dimensions are 1.25 x 1 x 0.8 or
1.66 x 1 x 0.6. These are known as the “golden ratios.” Under no
circumstances should the box be made in a “cube” shape with all
sides equal.
In applications which require multiple woofers, we
recommend a common cavity for each “pair” of woofers. This is
achieved by doubling the recommended enclosure volume. The
woofers should be physically positioned as close together as possible
to create an acoustic “coupling” of the two woofers, which will result
in an increase in output level.
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