DD Audio 9921C-D2 SuperCharged 21" 3200W RMS Dual 2 Ohm USA Built Subwoofer

• SUPERCHARGED MOTOR: A neodymium ring focuses magnetic energy into the voice coil gap for 20 to 25% more usable motor strength and tighter cone control.
• SAME 3200 WATT RMS RATING: Handles the same power as the standard 9921C, so the extra control comes without changing your amp requirements.
• MORE CONE, LESS TRAVEL: Up to 30% more cone area than a typical 18" lets it move big air with less coil movement.
• FLEXIBLE DUAL 2 OHM WIRING: Wire one sub to 1 or 4 ohms, or run two subs at 2 ohms or 0.5 ohm to match your amp.
• MADE FOR BIG PORTED BOXES: Designed for 6.0 to 8.0 cu. ft. ported enclosures in high-output builds.

DD Audio 9921C-D2 SuperCharged 21" 3200W RMS Dual 2 Ohm USA Built Subwoofer

This Listing Includes:

• (1) DD Audio 21" Dual 2-Ohm SuperCharged Subwoofer 9921C-D2, 3200W RMS / 9600W Peak, USA Built

Please note: SuperCharged subwoofers are made to order by DD Audio. Please allow approximately 1 to 2 weeks for your sub to be built before it ships.

The DD Audio 9900C Series 21-inch subwoofer is built for people who want deep, heavy bass and a lot of air movement. It's rated at 3200W RMS with 9600W peak power handling. The 9900C's large ferrite motor is made for clean output and real power, backed by the aluminum Dual Stage rear-mounted heatsink, USA-made Iron Cloth Spider System, and 2nd generation V-ROM surround for efficiency and durability. The 9921 adds a composite cone with up to 30% more cone area than a typical 18" sub. More cone area means it can move the same air with less coil travel, which helps it stay efficient and controlled. This sub is made for high-output ported enclosures.

This is the SuperCharged version. DD adds a specially shaped neodymium ring inside the motor that redirects magnetic energy into the voice coil gap, raising usable motor strength by about 20 to 25%. With a cone this size, that extra grip helps keep it tight and controlled across the whole power range. Power handling stays the same as the standard 9921C, so plan your amp around 3200 watts RMS.

Features

• SuperCharged Motor with Neodymium Flux Ring


• NEW Aluminum 2 Stage Motor Heatsink


• 260mm Magnet Diameter


• Multi-Vent Free Flow Cooling Motor


• Shorting Ring Motor


• 4.3" High-Temp Voice Coil


• Excursion Optimized ESP Frame


• V-ROM Vario-Density Surround


• Non-Pressed Composite Reinforced Pulp Cone


• 11" Dual/Triple Layer Iron Cloth Spider


• Laminated Tinsel Leads


• Hand Laid Composite Dust Cap


• Embossed DDesign Magnet Boot


• Made In USA

Specifications

• Speaker Size: 21 inches


• Watts RMS: 3200 (same as standard model)


• Watts Peak: 9600


• Impedance: Dual 2-ohm


• Voice Coil Diameter (VCD): 4 inches


• Piston Diameter: 18.25 inches


• Resonant Frequency (Fs): 26.24 Hz


• Qms: 5.265


• Qes: 0.517 (standard model)


• Qts: 0.471 (standard model)


• Vas: 161.9 liters


• Xmech (Max Excursion): 92 mm


• Xmax (Linear Excursion): 22 mm

Suggested Enclosure Specifications

• Woofer Displacement: 0.55 cu. ft.


• Recommended Ported Enclosure: 6.0 - 8.0 cu. ft.

Dimensions:

• Frame Outer Diameter (OD): 21.3125 inches


• Frame OD with Gasket: 21.3125 inches


• Mounting Diameter: 19.25 inches


• Mounting Depth: 11.3125 inches


• Motor Diameter: 10.3125 inches


• Motor Depth: 4.5625 inches


• Shipping Weight: 92 lbs

If you want the most cone area in the 9900 lineup with even more motor control, the SuperCharged 9921C is the one to grab.

Accepted Payment Methods at Big Jeff Audio

At Big Jeff Audio, we strive to make your shopping experience as smooth as possible by offering a wide variety of payment options. Below is a complete list of the payment methods we accept:

Credit and Debit Cards

• Visa
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International Payment Methods

• Bancontact
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Bank Transfers

• Zelle

Financing Options

We also offer financing options to make purchasing easier. Learn more about our financing options here.

• Klarna
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• Sezzle
• Snap
• Acima
• Tiptop

If you have any questions or need assistance with payments, feel free to reach out to us at info@bigjeffaudio.com or call us at 737-BIG-JEFF.

Shipping Options and Delivery Time

Do You Offer Expedited Shipping?

Yes! At checkout, you can select from different shipping options:

• Standard Shipping: Free for orders over $100.
• Expedited Shipping: Available at an additional cost, calculated based on the weight and destination of your order.

How Long Does Delivery Take?

• Handling Time: Most orders are processed and shipped within 1 business day after receiving cleared payment. Occasionally, additional handling time may be required, but we’ll notify you if that’s the case.
• Standard Shipping: Typically takes 3-5 business days, though delivery may be affected by extreme weather or holidays.

What Happens If My Package Is Undeliverable?

If your package is refused or marked undeliverable and returned to us by the carrier, you’ll need to pay the full shipping cost to have the package resent. Alternatively, we can refund your order, minus the cost of shipping.

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