Our Product Research Team
At Crutchfield, you'll get detailed, accurate information that's hard to find elsewhere.
That's because we have our own in-house Product Research team — they open the box,
verify contents, check the owner's manual, and record dimensions, features and specs.
We stay on top of new products and technologies to help people make informed choices.
Polypropylene Cone: The cone is made with polypropylene, which
provides durability while being lightweight and rigid. The cone is supported by
a vented cone/coil coupler, which stiffens the cone for greater mechanical
stability and lower distortion.
Surround: The Santoprene surround is resistant to extremes in temperature,
humidity, and exposure to sunlight for excellent long term reliability.
NOMEX Spider: The fire-retardant flat NOMEX
Spider allows extended linear motion while providing highly reliable mechanical
and thermal stability.
Triple-vented Kapton Voice Coil
Former: Triple venting of the 4-layer Kapton Voice Coil Former, Cone/Coil
Coupler and Pole Piece contribute to the high power handling and reliability of
the db Series subs.
Klippel Laser Analyzed: The Polk db woofer's voice coil alignment,
motor, and suspension are optimized using a state-of-the-art Klippel laser
analyzer for superior cone travel linearity, resulting in a flatter response
with lower distortion.
Break-In Period: Polk db subwoofers will achieve even greater
performance once they are thoroughly broken-in. To break in a new db Sub, play
music through it for 20 to 30 hours at moderate levels.
Recommended Sealed Box Volume: Polk recommends mounting this
woofer in a sealed enclosure made out of 3/4" MDF with an internal volume of
Recommended Ported Box Volume: Polk recommends a ported
enclosure made out of 3/4" MDF with an internal volume of 1.50 cu/ft using a
4" diameter x 10" long port.
Recommended Bandpass Box Volume: Polk recommends a bandpass
enclosure made of 3/4" MDF with a total internal volume of 2.15 cu/ft. The bandpass box
should have a 1.0 cu/ft sealed rear chamber and a 1.15 cu/ft ported front
chamber with a 4" diameter x 12" long port.