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Diamond Audio D308D4
D3 Series 8" subwoofer with dual 4-ohm voice coils
Our take on the Diamond Audio D308D4 by Crutchfield's Jo Greene
Rockin' D3 Series 8" sub
You hit the highway and crank the stereo, but your factory bass just can't keep up. Diamond Audio designed D3 Series subwoofers for high-performance bass in your car — you'll hear lots of heavy, powerful low notes that make for a very entertaining ride, even if it's just across town.
Heat dissipating woofer
This 8" D3 sub features a light, responsive copolymer cone and large-roll rubber surround for precise cone movement, so you can count on strong, accurate performance. The stamped aluminum dust cap directs heat away from the motor structure, and helps prevent heat from getting trapped in your subwoofer enclosure.
Aluminum voice coils stay cool
Diamond Audio furnishes this sub with hefty 2-1/2" aluminum-coated copper voice coils that dissipate heat for extended power handling. Proprietary Venturi venting in the basket and pole piece funnels warm air away from the sub's interior, and that means the sub stays cooler and happier. The dual 4-ohm voice coils give you more options for wiring the sub into your system, and make it easy to add a second D3 sub later on.
Non-resonant basket resists distortion
The heavy-gauge stamped steel basket gives this sub the strength and stability it needs to rock hard for the lifetime of your system. Diamond Audio forms this basket using a unique stamping technique that virtually eliminates unwanted resonance, so your favorite music sounds just as the artist intended.
Diamond Audio goes the extra step
In most subs, the spider assembly is glued to the basket. In D3 subs, Diamond Audio uses a dual spider assembly that is glued and screwed to the basket to virtually eliminate the possibility of mechanical failure.
What's in the Box:
- 8" Dual 4-ohm voice coil subwoofer
- Rubber trim-ring (installed)
- Installation manual
- 8" subwoofer with dual 4-ohm voice coils
- textured copolymer cone with nitrile butadine rubber surround
- heavy-gauge stamped steel basket
- power range: 20-200 watts RMS (400 watts peak power)
- frequency response: 30-500 Hz
- sensitivity: 83 dB
- top-mount depth: 4-1/8"
- sealed box volume: 0.5 cubic feet
- ported box volume: 1.0 cubic feet
- warranty: 1 year
- Our 60-day money-back guarantee
Features and Specs
|Impedance||2 ohms or 8 ohms|
|Cone Material||Textured copolymer|
|Ideal Sealed Box Volume (cubic feet)||0.5|
|Ideal Ported Box Volume (cubic feet)||1|
|Port diameter (inches)||3|
|Port length (inches)||7.5|
|Dual Voice Coil||Yes|
83.1 dB at 1 watt
|Frequency Response||30 - 500 Hz|
|RMS Power Range (Watts)||20-200|
|Peak Power Handling (Watts)||400|
|Top Mount Depth (inches)||4 3/16|
|Bottom Mount Depth (inches)||N/A|
|Cutout Diameter or Length (inches)||7 1/4|
|Parts Warranty||1 Year|
|Labor Warranty||1 Year|
Dual 4Ω Voice Coils: The D308D4 features dual 4Ω voice coils. When the voice coils are wired in parallel, the woofer presents a 2Ω load; when wired in series, the woofer presents an 8Ω load.
Cone: The textured copolymer cone has an aluminum dust cap to help draw heat away from the voice coil.
NBR Surround: The woofer features a Nitrile Butadiene Rubber (NBR) surround, a synthetic rubber that stands up to the harsh automotive environment.
Spring-Post Terminals: The spring-post terminals will accept pin connectors, single banana plugs, and bare wire up to 8-gauge.
Concealing Ring: The included rubber trim-ring provides a mounting gasket and covers the mounting screws, giving the subwoofer a finished look.
Sealed Enclosure: The recommended sealed box volume is 0.5 cubic feet.
Vented Enclosure: The recommended vented box volume is 1.0 cubic feet with a 3" diameter, 7-1/2" long port; resulting in a tuning frequency of 45 Hz. A 30 Hz sub-sonic filter is recommended for vented enclosures.
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 verify what’s in the box, 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.