DD Audio 21" USA Built Dual 2-Ohm 4” Voice Coil 3200-Watt RMS Subwoofer 9921C 

• Impressive Power Handling: 3200W RMS, 9600W peak for extreme bass output and efficiency.
• Innovative Cooling: Aluminum 2-stage motor heatsink and multi-vent Free Flow Cooling system for heat dissipation.
• Precision Excursion: 2nd Generation V-ROM and EROM surrounds for extended cone travel and minimal distortion.
• Durability and Control: 4.3-inch high-temp voice coil with a supercharged 9900 motor for tight, controlled bass.
• Enhanced Cone Area: Composite cone with 2nd generation EROM high-roll surround for more efficient air movement.
• Dual 2-Ohm Configuration: Perfect for flexible amplifier matching and enhanced performance.
• Handcrafted in the USA: Made with premium materials for exceptional sound quality and durability.

DD Audio 21"   USA Built Dual 2-Ohm 4†Voice Coil 3200-Watt RMS Subwoofer 9921C

This Listing Includes:

• (1) DD Audio 21" 2-Ohm, 3200 RMS/9600 Peak USA Built Subwoofer

The DD Audio 9900C Series 21-inch subwoofer is a powerhouse designed for those who demand deep, thunderous bass with unmatched efficiency. With an RMS rating of 3200W and a peak power handling of 9600W, this subwoofer is engineered to deliver the ultimate performance. The 9900C’s large ferrite motor series is built to provide exceptional sound clarity and power, even with intense power bursts over 12,000W. Utilizing cutting-edge technologies like the aluminum Dual Stage rear-mounted heatsink, USA-made Iron Cloth Spider System, and 2nd generation V-ROM surround, the 9900C ensures high efficiency, durability, and superior sound. The 9921 model expands on these features with a composite cone and 2nd generation EROM surround, offering up to 30% more cone area than typical 18†subwoofers. The result is more efficient air movement with less coil travel, providing an unbeatable audio experience. Perfect for high-output ported enclosures, this subwoofer is made to move air and produce the deepest bass with precision.

Features

• 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


• 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


• Qts: 0.471


• Vas: 161.9 liters


• Xmech (Max Excursion): 92 mm


• Xmax (Linear Excursion): 22 mm


• 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


• Woofer Displacement: 0.55 cu. ft.


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


• Shipping Weight: 92 lbs

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
• Mastercard
• American Express
• Discover
• Diners Club

Digital Wallets

• Amazon Pay
• Apple Pay
• Meta Pay (formerly Facebook Pay)
• Google Pay
• Shop Pay
• PayPal

International Payment Methods

• Bancontact
• iDEAL

Bank Transfers

• Zelle

Financing Options

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

• Klarna
• Affirm
• 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.

Why Can’t I Track My Order?

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• Make sure you’ve received the shipping confirmation email with the tracking number.
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• If the issue persists, please refer to our detailed guide on tracking your order or contact our customer service team for further assistance.