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Polk Audio db1240

360W 12" db Series Single 4 ohm Marine Certified Subwoofer

In Stock
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List price $119.99

$69.99

with warranty

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Arrives by Wednesday, Sept. 24 to zip 07095

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In Stock

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  • 12" Single 4 Ohm db Series Subwoofer
  • Power Handling:
    • Peak: 720 watts
    • RMS: 360 watts
  • Impedance: 4 Ohms
  • Polypropylene cone
  • Santoprene rubber surround
  • Completely marine certified
  • Integrates cutting edge technology for optimal bass performance
  • Designed for sealed or ported enclosures
  • Mounting depth: 6-1/16"
  • Frequency response: 27-200 Hz
  • Sensitivity: 88 dB
  • db Series Subwoofer Grill Available
  • 1-year SonicElectronix.com warranty

Product History:

Polk Audio db1240 thumbnail
(newest, current model)
Polk Audio db124 thumbnail
(previous model, replaced by Polk Audio db1240)

Subwoofer Specifications

Subwoofer Series
Each subwoofer manufactured is part of a series. This is the name of the subwoofer's series.
db (Polk)
Subwoofer Size
Refers to the diameter of the subwoofer, measured in inches.
12"
Peak Power Handling
Peak power handling refers to the amount of power a speaker can handle during a brief musical burst. The RMS power range figure is a much more reliable rating for determining the speaker's power requirements. The Peak power handling specification is typically rated per speaker unless otherwise noted.
720 watts
RMS Power Handling
The RMS power is the amount of power the speaker requires to operate safely and properly. RMS Power Handling refers to the amount of power a speaker can handle on a continuous basis. We recommend powering your speakers or subwoofer with 80%-120% of its recommended RMS rating. The RMS power handling specification is typically rated per speaker unless otherwise noted.
360 watts
Voice Coil(s)
Dual voice coil subs have more wiring flexibility than single voice coils subs; however, single voice coil subwoofers provide easier hookup options for wiring multiple subwoofers in parallel or series. You may also run a dual voice coil (DVC) sub in parallel, series, or combination. A quad voice coil has four voice coils and is equal to two dual voice coil subwoofers as far as wiring goes.
Single
Impedance (Per Voice Coil)
The load value (in ohms) that the speakers present to the amplifier per voice coil - the amount of resistance to the current flow. This is a key specification as subs wired in parallel or low impedances can create problems with your amplifier and potentially void all warranties. We encourage you to ask our support department prior to purchase if you do not understand which impedance level will suit your application best.
4 ohms
Voice Coil Diameter
Diameter of voice coil, usually measured in inches.
Frequency Response
The range of frequencies the speaker will reproduce (lowest frequency to the highest). Bigger is better, meaning the wider the range, the better. The optimal range is 20 - 20,000 Hz (which is the range of human hearing).
27 - 200 Hz
Sensitivity
An efficiency or sensitivity rating tells you how effectively a speaker converts power into sound. The higher the number, the more efficient the speaker and the louder it will play with the same input power. An efficient speaker helps you maximize your available power. Most sensitivity ratings measure the speaker's output with 1 watt of input, 1 meter from the speaker. Some speakers' sensitivity is measured with 2.83 volts of input, instead of 1 watt.
 
Efficiency (1w/1m) is not an accurate indicator of a subwoofer's output capability and should not be used as a comparison to other speakers or subwoofers to determine which one is "louder".
88 dB
Xmax (millimeters)
Typically measured in millimeters, the Xmax value is the measure of a speaker cone's maximum excursion in one direction while maintaining a linear behavior.
7.5 mm
Subwoofer Design
This is the design of the subwoofer or the opening of the subwoofer enclosure. Each design has it's own benefits, whether it is a square, circle, or oval.

Round/Circle: This is the typical and common subwoofer design. They have a round cone and are a circle in design.

Square: These woofers are able to achieve a greater cone area in a smaller space. Because of the greater surface area, some square subwoofers will be louder than a round subwoofer of the same size.

Round / Circle
Main Cone Color
This is the color of the speaker's or subwoofer's cone.
Black
Woofer Composition
Lightweight woofer cone materials are essential for efficient operation. Poly cones produce exceptional sound and are sturdy against various changes in temperature. Paper cones are very efficient, and when treated for moisture resistance, will perform at a high level. Poly refers to polypropylene, which is thermoplastic or fibers that are polymers of propylene. IMPP refers to injection molded polypropylene, a commonly used process and material in speakers.
Polypropylene
Woofer Surround
A speakers surround is part of the suspension system. The surround protects the cone and prevents it from being displaced as it flexes out from the basket. It is usually made of a durable material like treated foam or rubber in order to withstand the strenuous job of producing bass frequencies.
Santoprene Rubber
Magnet Structure
Defines the overall structure of the subwoofers magnet.
Subwoofer Grille
Most subwoofers are able to accommodate a universal grille; however, some subs include a grille and others have a specific, optional grille available for purchase separately. If "yes", then the subwoofer includes a grille. If "optional (sold separately)" the matching grille will need to be purchased in addition to the sub.
No
Re-Cone Kit Available
Some higher end subwoofers have replaceable cone assemblies. In case of a blown woofer, a recone kit allows for a simple replacement, as opposed to purchasing an entire new subwoofer.
No

Recommended Enclosure Specifications

Recommended Enclosure Type
This is the recommended type of enclosure that the subwoofer should be installed into. Some subwoofers are specially designed for particular enclosures.

Sealed: These enclosures completely enclose the air inside the box. These boxes produce a tight bass.

Ported/Vented: These enclosures have a slot of air to escape from the box. The result is a sound that has more "boom".

Bandpass: These are a combination of both sealed and ported enclosures. They can be very efficient, but require tuning for the best response.

Ported / Vented
Sealed
Minimum Sealed Box Volume
This value indicates the minimum sealed box volume that the manufacturer recommends for the subwoofer. The volume is typically displayed in cubic feet.
.88 cubic feet
Optimum Sealed Box Volume
This value indicates the ideal sealed box volume that the manufacturer recommends for the subwoofer. The volume is typically displayed in cubic feet.
Maximum Sealed Box Volume
This value indicates the maximum sealed box volume that the manufacturer recommends for the subwoofer. The volume is typically displayed in cubic feet.
.88 cubic feet
Minimum Ported Box Volume
This value indicates the minimum ported box volume that the manufacturer recommends for the subwoofer. The volume is typically displayed in cubic feet.
1.5 cubic feet
Optimum Ported Box Volume
This value indicates the ideal ported box volume that the manufacturer recommends for the subwoofer. The volume is typically displayed in cubic feet.
Maximum Ported Box Volume
This value indicates the maximum ported box volume that the manufacturer recommends for the subwoofer. The volume is typically displayed in cubic feet.
1.5 cubic feet
Top-Mount Depth
The depth when installed on top of the mounting surface. Measured from the bottom of the speaker's magnet to the bottom of the mounting holes on the rim of the speaker.
6-1/16"
Cutout Diameter
The actual diameter of the hole you will need to cut out if you are creating a new mounting location for this speaker, or if you are mounting a subwoofer in a box.
11"
Shallow Mount Installation
This means that the subwoofer/speaker is designed to be installed in areas that do not have a lot of space. Shallow mount subwoofers are typically found under a seat or behind the seat in some trucks.

Shallow mount speakers will typically have a mounting depth of 2" or less, while shallow mount subwoofers will typically have a mounting depth of 3" or less.

No

Electromechanical Parameters

Free-Air Resonance (Fs)
The free-air resonance frequency of the subwoofer, measured in Hz. At this frequency the weight of the moving parts is perfectly balanced with the subwoofers suspension system.
Equivalent Compliance (Vas)
This is the amount of air that has the same stiffness as the subwoofers suspension. The greater the rating, the lower the stiffness and larger recommended enclosure. It is measured in Liters.
Total Speaker Q Value (Qts)
This is the subwoofers relative damping (Q) at the resonance frequency (Fs), including all dimensionless losses. Essentially, a high Qts value (closer to 1.0) means the subwoofer is great for sealed enclosures and a low Qts value (closer to 0) means the woofer is great in vented enclosures. A Qts of around 0.45 means the woofer will work decently in either enclosure type.
Electrical Q Value (Qes)
The subwoofers relative damping (Q) at the resonance frequency (Fs), including electrical losses. Also called the mechanical damping of the subwoofer. The unitless measurement usually varies from 0.5 10.
Electrical Resistance of Voice Coil (Re)
Amount of DC resistance of the subwoofer when measured with an ohm meter. Typically, this will read less than the impedance rating of the subwoofer.
Mechanical Q Value (Qms)
This is the subwoofers relative damping (Q) at the resonance frequency (Fs), including mechanical losses. Also called the mechanical damping of the subwoofer. This unitless measurement usually varies from 0.5 10.
Efficiency Bandwidth Product (EBP)
This number represents the trade off between having an efficient woofer and one with a wide bandwidth. To calculate this number, take the Fs and divide it by the Qes. If the number is below 50, the woofer is designed for a sealed enclosure only. If it's between 50-100 it can be used in either. Lastly, if it's greater than 100 it's designed for vented enclosures.

Specials with this Item

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Warranty and Return Policy

Parts Warranty Duration
1 year
Labor Warranty Duration
1 year
Warranty Provider
Sonic Electronix

Summary of Customer Ratings & Reviews

Rating Distribution

5 Star
73%
4 Star
27%
3 Star
0%
2 Star
0%
1 Star
0%

Average Attribution Rating

Durability
4.6
Value
4.8
Features
4.1
Design
4.7
Usability
4.5
Branden

Ridgecrest, CA

Overall
Durability
Value
Features
Design
Usability
polk audio db1240

July 3, 2014

I was looking for some new subs after my lanzer max st blew out, I got two of these subs and the sound way better have a deeper sound and shakes my truck a lot more then the lanzers did, buy these subs they are worth the money and feel amazing

0 of 0 found this helpful

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Jeff

MD

Overall
Durability
Value
Features
Design
Usability
Bump hard

October 10, 2013

These Polks sound great and definitely bump hard and handle the power with ease. Great freq response in a sealed box

0 of 0 found this helpful

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Justin

magalia, CA

Overall
Durability
Value
Features
Design
Usability
Awesome product

November 11, 2012

I bought a complete sound system for my car a few months ago and I was a little worried that only a 12 inch sub wasn't going to do much...I was wrong! This sub is awesome and is a lot more powerful than I thought.

0 of 0 found this helpful

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Palgume

Baltimore MD

Overall
Durability
Value
Features
Design
Usability
awesome

September 6, 2012

installed in home subwoofer 150 W rms and could not love it more awesome low Response

0 of 0 found this helpful

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808Mag

Kona, HI

Overall
Durability
Value
Features
Design
Usability
Precise

April 24, 2012

I have 2 of these on a Boston GT-2200 and they are loud and accurate. Granted I have them on a very good amp but they deliver on both sound quality and punch. They hit very hard but are stil able to make good midbass hum. The only complaints I have is that you have to use quick slides to connect your speaker wires and the screws are allen wrench but other than that these a great subs.

0 of 0 found this helpful

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808Mag

Kona, HI

Overall
Durability
Value
Features
Design
Usability
Accurate Bass

April 20, 2012

I have a pair of these on a Boston GT-2200 in the trunk of my Mazda 3 in a sealed box. The gain is less than half and are wired at 2ohm getting around 900 RMS to the pair and they sound very clean. I had more of an SPL setup before I got these and I wanted to get more sound quality then rattle. These aren't even broken in yet and they hit pretty good. I switched from a class d monoblock to this Boston class A/B and I dont think I am going back anytime soon. Can't wait till they break in so I can let them buck. If you dont have money for a good amp and care more about booming get the kicker comps. Couple things I dont like about them is they dont hit the higher mid bass notes all that great but maybe I just need more fiberfill but as I said earlier I havent broken them in yet. Also the cone material is pretty light compared to the last subs I had (polypro vs hemp fiber glass) I would suggest purchasing the grills. Lastly to hook these up I had to purchase quick slides, would be nice if they accepted bare wire like most of the new school subs. They also use allen wrench screws which I thought was rather strange.

0 of 0 found this helpful

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Jesus Burgess

Bay City, Michigan

Overall
Durability
Value
Features
Design
Usability
Great Buy

March 29, 2012

I had bought 2 of these subs in the box built to spec by Polk, and wow was I blown away. Had them at 2 ohms on an alpine mrp-500(500 rms at 2ohms) and they could easily take more. Not to mention the sound quality is some of the best I've heard. Had them in my 96 accord with Alpine 6.5s, Alpine 6x9s, and a Sony gtr-550 head unit. Was an amazing set up, with pristine sound quality, for a decent price.

0 of 0 found this helpful

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Jack

Wichita, KS

Overall
Durability
Value
Features
Design
Usability
Polk Audio db1240

December 15, 2011

I really didn't expect much when I got this sub, but I figured I'd give it a try. WOW... I LOVE this sub! I have Alpine Type-R 6.5's and 4x6's in my truck, my amp is an SPL Dynamics Z2X-820, and I made a 0.88 ft^3 sealed box (Polk's recommended). I have the sub bridged to the amp, with the gain about 3/4 and the sound quality is unmatched. Very good design, doesn't get hot, and keeps up with every style of music. This sub blends so well with my Type-R's, it brings a tear to my eye. However, run the gain on the amp at full twang, filter out anything above 50hz, turn off everything that enhances bass, and she will do work. I have the sub and box mounted on top of the back seat (with hopes that the cushion would absorb some of the rattling) and my iPhone jumps around in my dash.

0 of 0 found this helpful

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Robert

Orlando

Overall
Durability
Value
Features
Design
Usability
Polk Audio db1240 subwoofer

April 17, 2011

This subwoofer provides a good thump for its price which I would highly recommend.

0 of 0 found this helpful

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Jeffrey

Spring Hill, KS

Overall
Durability
Value
Features
Design
Usability
Great bang for the buck...

March 28, 2011

I have a pair of these subs with 350 watts on them. A good pair of basic subs. More of a sound quality piece than an spl one. Very low air space was an important factor for me, at .88 each sealed, these fit the bill. I have learned that a 12 inch sub is perfect for me. This is my 10th plus set of subs.

0 of 0 found this helpful

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George

Austin,MN

Overall
Durability
Value
Features
Design
Usability
pretty good sub for value

July 22, 2010

So far so good i've only owned them for like a month now. I bought 4 of these subs for my 05 navigator running them with a 1500 watt rms power bass mono amp in a custom fiberglass box and they hit pretty good! all i gotta say is that you can hear me coming from a couple blocks away!!

0 of 0 found this helpful

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Accessory Tools and Products

Accessories added

Single 12" Subwoofer Angled Truck or Hatchback Box Enclosure

CARB Compliant, 5/8" MDF Shallow Sub Enclosure Lined with Polyfil.

Your Price $34.99

12" SingleHatchback Style Small Sealed Subwoofer Enclosure

CARB Compliant, 3/4" MDF Dual Hatchback Style Sealed Enclosure w/ Premium Carpeted Finish

Your Price $42.95

12" Vented Subwoofer Enclosure

CARB Compliant, 3/4" MDF Vented Enclosure Lined with Premium Carpeted Finish

Your Price $65.95

25 ft. of Streetwires 12 Gauge Speaker Cable

You'll need speaker wire to hook up that new subwoofer!

Your Price $44.95

Belva 23 ft. of 12 Gauge Speaker Wire

Ultra-flexible PVC blended jacket for easy installation.

Your Price $14.99

20 Square Feet of Sound Dampening Material

NVX Sound dampening is thicker than competitors, eliminates rattles and gives you bigger bass!

Your Price $59.99

Dynamat Sound Dampening Trunk Kit

Did you know sound dampening will reduce those annoying rattles and even increase your SPL?

Your Price $109.95

Stinger Sound Dampening Trunk Kit

Stinger's Roadkill sound dampening series is sure to kill unwanted road noise and rattles! Enough sound dampening for your whole trunk!

Your Price $69.99

12 oz. Can of Adhesive Spray

Spray adhesive used for adhering carpet to subwoofer boxes without bubbles.

Your Price $6.99

Spring Post Terminal Cup

Makes adding a spring post terminal to an enclosure simple! Banana clip ready!

Your Price $3.99

40" x 15 Ft Piece of Premium Un-Backed Automotive Trim Carpet

Durable design for long life-span, available in many colors and shades.

Your Price $39.99

Gold Plated Dual Terminal Banana Plug Connector

Enables an expandable, secure connection accepting up to 8 gauge wire.

Your Price $1.99

Car Stereo and Speaker Installation Tool Kit

Includes Test Light, Crimp/Splice Tool, Multi-bit Screwdriver and more.

Your Price $12.99

Xscorpion 9-Piece Nylon Plastic Pry and Chisel Tool Set

Easily removes dash/trims, door clips, panels and pins, rubber grommets and vehicle emblems.

Your Price $14.99

Cordless Multi-Functional Heat Tool Soldering Iron Kit

Continuous working lock allows you to work without holding down trigger.

Your Price $79.99

4 Ft of 1/4" Thick Black Heat Shrink Tubing

Provides abrasion resistance and added protection for your cables.

Your Price $3.99

2" Universal, Professional Heavy Duty Roller for Sound Damping/Dampening

Universal rubber roller to make it easy to install sound dampening.

Your Price $7.99

1mm All Purpose Solder

Solder is all purpose for use on most projects where solder is needed.

Your Price $8.99

Polk Audio DB12G

12" db Series Subwoofer Grille

Your Price $20.99

12" Protective Waffle Subwoofer Grille

Keep your subwoofer looking amazing while keeping it safe.

Your Price $4.99

Scosche SPL Meter

Monitor the noise level of your new car audio system with this SPL meter measuring from 60-135 dB.

Your Price $21.99

Impedance Meter / Signal Generator

Easy to locate tuning frequencies of passive radiators and ported enclosures

Your Price $299.99

1 Polk Audio db1240 Subwoofer

Mono Amp

2 Channel Amp - Bridged

2 Polk Audio db1240 Subwoofers

Mono Amp

2 Channel Amp

4 Channel Amp - Bridged

3 Polk Audio db1240 Subwoofers

4 Channel Amp

4 Polk Audio db1240 Subwoofers

Mono Amp

Mono Amp - Option 1

2 Channel Amp

2 Channel Amp - Bridged

4 Channel Amp

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• 540W Peak
• 270W RMS
• Single 4 Ohms
• Polypropylene Cone
• Santoprene Rubber Surround
• Marine Certified

Your Price $59.99

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Product Summary

Manufacturer

Model Number

db1240

UPC

747192113803

Weight

14.00lbs

Internal SKU

db1240

Internal Product ID

18187

Sonic Electronix Wiring Guide

Wiring Diagram Legend

Warning: The image depicted shows the resistance change when wiring multiple subwoofer terminals. Please refer to your subwoofer's owner's manual for the proper wiring of its terminals. Sonic Electronix, Inc. is not responsible for damage caused to your audio system or vehicle due to improper installation. Please call tech support at 1-877-289-7664 if you require additional assistance.

Product Name: Polk Audio db1240