Cone Cosmetics and Materials:
The woofer cone is made of Mica-filled polypropylene with an aluminum finish
with 12 stiffening ribs for improved cone stiffness and higher mechanical power
handling; the ribs increase cone durability and performance. Concentric
rings are molded into the cone and dust cap surfaces to give them a machined
appearance. "MTX Audio" is embossed on the poly dust cap.
12-leg Die Cast Aluminum Basket: The
basket was built with the strength and stiffness required to handle the demands
of enormous bass without flex or distortion.
Oversized Magnet Structure:
This woofer has an oversized magnet structure, made with a 102 oz. Strontium
NBR Rubber Surround: The woofer
is made with a one-piece NBR (Nitrile Butadiene Rubber) surround and gasket
combination. When bottom-mounting the woofer, the one-piece surround and
gasket make an air-tight seal, to prevent any loss of performance due to air
leaks around the woofer. When the woofer is top-mounted, the one-piece
surround and gasket combination enhances the overall cosmetic appearance of the
woofer. NBR has the added benefit of being resistant to ozone and UV rays
for extreme durability.
Computer Optimized Progressive
Roll Spider (COPR): A "five roll" spider design is used
to maximize the linear region of the speaker's movement.
Four-layer Voice Coil: A
2.5" four-layer voice coil is used for higher power handling.
Spider Plateau Venting: Small
vents are located around the base of the frame to prevent hot air from being
trapped between the spider and the back plate. The vents help cool the voice
coil to increase power handling and reliability.
Asymmetrical Linear Drive: This
system improves linearity and permits high output with low distortion.
Extended Pole Piece: The
extended pole piece provides a more symmetrical magnetic field.
Spring Post Inputs: The inputs
are spring post connectors that will accept bare wire, tinned wire or wire
terminated with pin connectors.
Enclosure Compatibility: This
woofer can provide extended bass in sealed, vented and bandpass enclosures (see
below for more information on enclosures).
Recommended Sealed Box
Volume: The sealed box sizes recommended by MTX range from 0.5 cu/ft to
1.0 cu/ft. The sealed enclosure MTX highlights on their spec sheet is a
0.63 cu/ft enclosure, so this is the enclosure recommended by Crutchfield.
Vented Box Volume: The
vented box sizes recommended by MTX range from 1.0 cu/ft to 2.0 cu/ft. The
vented enclosure MTX highlights on the woofer specification sheet is a 1.25
cu/ft enclosure, so this is the enclosure recommended by Crutchfield. A
3" diameter x 16" long port should be used with a 1.25 cu/ft
enclosure; a 1.25 cu/ft enclosure with a 3"x 16" port has a tuning
frequency of 31 Hz.
Single Reflex Bandpass Volume:
The bandpass box sizes recommended by MTX range from 0.66 cu/ft to 1.15
cu/ft. MTX highlights two bandpass enclosures on the woofer specification
sheet. One highlighted enclosure has an "S" value of 0.6, and
the other highlighted enclosure has an "S" value of 0.7. The
highlighted bandpass enclosure with an "S" value of 0.6 is a 0.77
cu/ft enclosure, with a sealed chamber volume of 0.23 cu/ft, a vented chamber
volume of 0.31 cu/ft and a 4" diameter x 19" long port. The
enclosure with an "S" value of 0.7 is a 0.91 cu/ft enclosure, with a
sealed chamber volume of 0.28 cu/ft, a vented chamber volume of 0.43 cu/ft and a
4" diameter x 16" long port.
Note: The bandpass
enclosure with the higher "S" value produces a more narrow bandwidth
with better transient response; the enclosure with the lower "S"
value produces a wider bandwidth at the expense of transient response.