5-1/4 inch coaxial mobile loudspeaker

5 1/4" coaxial
13.34cm coaxial


$9995 per pair

Available Finishes:
Additional Images

Your Ride, Our Sound. Even Sweeter.

This bad boy slips easily into a door and like all DXi loudspeakers delivers the awesome sound quality people have come to expect from Polk. Of course DXi521 comes with the full complement of exclusive Polk features that make it an exceptional value for the price.

DXi521 Features:

Klippel motor optimization uses laser measurement technology to ensure a smooth excursion path at either end of the volume spectrum for uniform performance at both low and high volumes.

Polk’s proprietary, patented Dynamic Balance® technology allows our engineers to design out distortion-causing driver and system resonances, so you only hear the good sounds.

Composite cones feature tremendous stiffness-to mass ratio; the cone’s lower mass translates into faster transients and finer detail.

Aluminum dome tweeter easily handles higher volume levels and also offers a higher power handling capability.

All Polk products are made using the best materials and the most advanced manufacturing techniques. They pass the industry’s most exhaustive quality tests, including drop testing, extreme signal response and UV & salt exposure testing. Polk loudspeakers are built to perform for a lifetime.

Driver Complement

Diameter3/4" (1.91cm) 
TypeDynamic Balance aluminum dome 
Mid / Woofer
Diameter5 1/4" (13.34cm) 
TypeDynamic Balance polypropylene cone 


Total Frequency Response60Hz-22kHz 
Nominal Impedance4 ohms
Efficiency93 dB
Power Handling
Continuous45 watts
Peak135 watts


Cut-Out Diameter4 3/4" (12.06cm) 
Height7/8" (2.22cm) 
Full-Range Mounting Depth
Top Mount2 5/16" (5.87cm) 


Unit of Measurepair 
Total Shipping Weight4.5 pounds


Speaker Warrantyone year parts and labor (original purchaser) 

Specifications, dimensions and features subject to change without notice. For more information call us at 1-800-377-7655 (USA and Canada). Outside of North America call +1 (410) 358-3600.

DXi521 Media

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