What's a component sub and why would I want one?

A component sub is simply a speaker that's designed to reproduce bass once it's installed in a compatible enclosure. Think about the impact of a movie soundtrack in a big theater or even in your own home HDTV setup. A component sub can add the same kind of power to the music in your car. And a car sub is not all about the boom that you hear on a street corner (although that's cool too) - you can pair a component sub with your choice of enclosure to get bass just the way you like it, from tight and punchy to fat and loose. And once you experience music in your car with a well-tuned subwoofer, you'll never go back.

Our take on the Focal Utopia Be® 21 WX

by Dominic Devito

Focal's top-of-the-line Utopia Be speakers exemplify Focal's dedication to musical perfection. The sound enthusiasts at Focal worked without constraints to develop what they consider to be the ultimate in speaker technology. Utopia Be subwoofers employ unique materials and unparalleled construction to add incomparable dynamics and natural sound to your system.

Focal's composite sandwich "W" cone features a layer of durable structural foam between two layers of precision-coated glass — the resulting membrane demonstrates exceptional agility, rigidity, and damping to produce realistic bass notes without distortion. A supple rubber surround maintains precise control over the cone, even during extreme excursion. A massive multi-element magnet, high-linearity voice coil, and zinc alloy basket give the sub rock-solid power and strength.

The Utopia Be 21 WX 8" subwoofer represents the pinnacle of Focal's pursuit of perfect-sounding, full-bodied bass. It handles up to 250 watts RMS and works best in compact sealed enclosures. Utopia is defined as an "ideal place or state," and these hand-crafted Focal subs let you take your music to that level.

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Highlights:

8" 4-ohm subwoofer
"W" structured foam and glass composite sandwich cone with rubber surround
zamak (zinc alloy) basket
multiferrite magnet
power handling: 50-250 watts RMS (500 watts peak power)
frequency response: 29-500 Hz
sensitivity: 82.63 dB
top-mount depth: 4-3/16"
sealed box volume: 0.52-1.06 cubic feet
warranty: 1 year
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Priced per speaker

Hands-on research from the Crutchfield Labs (what are the Labs?)

Features and specs chart | What’s in the box? | In-depth notes

Features and Specs


Size Loading...	8 -inch
Impedance Loading...	4 ohms
Cone Material Loading...	Glass/foam composite
Surround Material Loading...	Rubber
Ideal Sealed Box Volume (cubic feet) Loading...	N/A
Ideal Ported Box Volume (cubic feet) Loading...	1.06
Port diameter (inches) Loading...	N/A
Port length (inches) Loading...	N/A
Free-Air Loading...	No
Dual Voice Coil Loading...	No
Sensitivity Loading...	86.5 dB at 2.83 watts 82.63 dB at 1 watt
Frequency Response Loading...	29 - 500 Hz
RMS Power Range (Watts) Loading...	50-250
Peak Power Handling (Watts) Loading...	500
Top Mount Depth (inches) Loading...	4 3/16
Bottom Mount Depth (inches) Loading...	4 5/8
Cutout Diameter or Length (inches) Loading...	7 3/16
Vas (liters) Loading...	18.8
Fs (Hz) Loading...	36.63
Qts Loading...	0.6
Xmax (millimeters) Loading...	8.5
Parts Warranty Loading...	1 Year
Labor Warranty Loading...	1 Year

Product Research

What's in the box?

Download owner's manual

One 8" Single voice coil 4-ohm woofer
Six 7/8" Hex-head mounting screws
Grille
Adhesive backed foam gasket
User manual
FOCAL logo sticker

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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.

Features
Enclosure Compatibility

Features

"W" Composite Sandwich Cone Woofer: The Focal 21 WX Be 8" subwoofer features a "W" composite sandwich cone woofer. The rigidity of the glass layers delivers extreme linearity over a wide frequency range without and low frequency distortion. The structural foam central core's lightness allows optimal acceleration, without delay, while damping derived from the "W" material produces a neutral, coloration free sound.

Rubber Surround: The long-throw rubber surround provides long excursion, deep bass (29-500Hz), and added durability to promote long life.

Multi-Ferrite Magnets: The woofer utilizes six double-stacked Ferrite magnets (12 total) to create a powerful magnetic field to help suppress compression and offer better power handling. The Multi-Ferrite motor assembly also aids the natural cooling of the woofer's voice coil.

Die Cast (Zamak) Vented Basket: The 21 WX Be features a vented die-cast Zamak basket which is a rigid, non-magnetic, and non-resonant frame that provides a strong, reliable structure for the woofer. The vented basket provides a self-regulated coil cooling system which allows air to flow freely, preventing heat build-up.

Spring Posts: The wiring terminals are spring posts which accommodate pin connectors, single banana plugs, dual banana plugs (standard 3/4" width) or bare speaker wire up to 10 gauge.

Enclosure Compatibility

Sealed Enclosure: The two sealed enclosure volumes Focal recommends are 15 liters (0.53 ft³, resulting in a -3dB point of 45 Hz) and 30 liters (1.06 ft³, resulting in a -3dB point of 43 Hz).

Ported Enclosure: The Focal recommends a ported enclosure of 30 liters (1.06 ft³) with a 2" diameter x 5-1/4" long port tube, resulting in a tuning frequency of 34 Hz and a -3dB point of 29 Hz.

Product reviews from the Crutchfield Labs (what are the Labs?)

Video: Introduction to Focal Car Audio

Zak Billmeier, Ken Nail

4/14/2009

Crutchfield's car audio experts Ken and Zak present an overview to Focal car audio products. Focal is a leading name in high-quality sound and Crutchfield is proud to have them in our lineup.