Skip Navigation

Polk Audio db1240

db Series 12" 4-ohm subwoofer

Item #: 107DB1240

In Stock

10 Reviews | Ask Questions


Price Break:-$30.00

Your price: $69.99 Earn up to 70 Rewards points

Add to Cart

+ Add to wishlist + Email me alerts for this product

View all associated offers

Polk Audio's db Series subwoofers give you trademark Polk performance without stressing your wallet. These subs combine high-tech materials with a laser-optimized motor structure for smooth, powerful bass response.

The db1240 12" subwoofer boasts a rigid polypropylene cone and durable Santoprene™ surround built to handle big power over the long run. Polk Audio tests their subs rigorously to ensure that they stand up to sunlight, moisture, and extreme temperature changes.

Match a db sub to a suitable enclosure, and enjoy impressive low-frequency performance rarely found in this price range.

Priced per speaker

Product Highlights:

  • 12" 4-ohm subwoofer
  • polypropylene cone with Santoprene rubber surround
  • power range: 50-360 watts RMS
  • peak power handling: 720 watts
  • frequency response: 27-200Hz
  • sensitivity: 88 dB
  • top-mount depth: 6-1/16"
  • sealed box volume: 0.88 cu. ft.
  • ported box volume: 1.5 cu. ft.
  • warranty: 1 year
  • Our 60-day money-back guarantee

What's a component sub and why would I want one?

A component sub is simply a speaker that's designed to reproduce bass once it's installed in a compatible enclosure. Think about the impact of a movie soundtrack in a big theater or even in your own home HDTV setup. A component sub can add the same kind of power to the music in your car. And a car sub is not all about the boom that you hear on a street corner (although that's cool too) - you can pair a component sub with your choice of enclosure to get bass just the way you like it, from tight and punchy to fat and loose. And once you experience music in your car with a well-tuned subwoofer, you'll never go back.

Polk Audio db1240 Reviews

Average Customer Review:

10 Reviews

Great Subs for tight space and bass

Written by: Sane Jaxon from Castalian Springs, TN on December 4, 2012

Crutchfield Customer Review (What's this?)

  • Not Rated
    "Coolness Factor"
  • Not Rated
    Build Quality
  • Not Rated
    Ease of Use
  • Not Rated
    Sound Quality
  • Not Rated

Great Subs that provide really tight bass as well as hitting those good low ends. I was surprised at the bass delivered in such a small space as my 03 2 door jeep tj.

Pros: Really punchy bass, good delivery of low end notes, not a lot of air space required

Cons: none...


Written by: Joerocket from Sophia, WV on July 15, 2012

Crutchfield Customer Review (What's this?)

  • "Coolness Factor"
  • Build Quality
  • Ease of Use
  • Sound Quality
  • Value

Always the best speakers,put them in a redone 88 f150,sound great as always, this wasnt my first polks and wont be the last.

Pros: Good price,great quality,great sound

Cons: None


Written by: Rob from Kona, HI on May 1, 2012

Crutchfield Customer Review (What's this?)

  • "Coolness Factor"
  • Build Quality
  • Ease of Use
  • Sound Quality
  • Value

I listen primarily to Hip Hop, R & B, Dubstep, Reggae and Hawaiian and in their dual sealed box they perform outstanding. If I want to I can flex the roof and windshield of my car no problem. I would not however recommend them for a beginner to car audio because they have very little distortion around their rated power which to the beginner is perceived as lower output. Creating a tendency to turn up the gain, bass boost and volume to compensate. So if you want to slap these might not be the best for you. If you care about the details of my setup and how I use them to make my system sound great read on...

The pair of DB1240's is connected to a Boston GT-2200 amp hooked up with 4 gauge power and ground 1.2 farad Tsunami cap in the trunk of my Mazda 3 sedan. They are getting a rated 900 watts rms to the pair so factor in voltage drop and it's more like 800 rms so around 400 watts rms to each, ballpark. If you have a good quality amp and set your gains properly and don't clip your signal they will handle more than their RATED power and excel. The bass is tight and detailed dropping to pick up low rumbling sub bass sections while still being able kick you in your chest on higher notes and even picking up a nice hum on mid bass to blend with my front sound stage.

Throw these on a quality amp and tune it correctly and you will be happy. 4 stars because well only the Funky Pup subwoofers could ever really achive a true 5 star rating...

Pros: Sound Quality, Clean simple design, powerful, directions come with recommended X-Over settings for sub as well as front soundstage.

Cons: Quick slides, allen wrench screws

Not what I expected

Written by: Kevin from Crystal Lake IL on August 18, 2011

Crutchfield Customer Review (What's this?)

Once I had the subs installed I was happy that I finally had some 'hit' back into my stereo, however the hit was not as I wanted. I listen to music that has some soft hits that my past subs would have picked up and slammed on however these subs don't pick up the little hits and that was what I was looking for....



Great sound

Written by: Rich from Riverside, CA on March 20, 2011

Crutchfield Customer Review (What's this?)

I purchased this sub to replace an old Pioneer I had, and it sounds great! I'm
into jazz and old school R&B, this sub brings out the best in this type of music.
Crutchfield, really came thru.




Written by: Gaudecio from Northern Marianas Island on February 12, 2011

Crutchfield Customer Review (What's this?)

very nice thank you keep up the good work!!!very fast shipping



Nice Tight Bass

Written by: Adam from Indianapolis,IN on February 24, 2010

Crutchfield Customer Review (What's this?)

I recently damaged my Powered 12" JBL Northridge 8 ohm Home Audio Woofer and replaced with this 4 ohm Polk db1240. The JBL Northridge has a 250 watt rms, 550 peak power 8 ohm amplifier but, this Polk woofer matchs up perfect and sounds great!



Great Sub

Written by: labmaster66 from Dubuque, IA on June 4, 2009

Crutchfield Customer Review (What's this?)

I purchased these with the recommendation by a Crutchfield advisor and I am very pleased. I put these in an airtight enclosure built to the manufacturers recommended size and I am pushing them with a 600 watt amp. I am not disappointed. I replaced a blown pair of 10 inch and these Polk Audios blow them away. Thank you Crutchfield for another fine product. My Crownline boat sounds awesome and I get a lot of compliments on the quality of the sound system.




Written by: Shawn from Chicago on May 23, 2008

Crutchfield Customer Review (What's this?)

Pushing this with a 150 watt home amp (AC powered of course) it WILL and does, push it to it's max. In a box with isolation spikes all sealed but the 10" X 4" port. 1.3 cu ft. Other things I use , Denon reciever, Polk monitor 50's front and back... sorry I forget the model, center channel w/ 2 5 1/4's. Never go out and buy a powered sub unless you want quality. So easy to make a GREAT one yourself!



Gr8 Sub

Written by: sugam from New Delhi , India on March 31, 2008

This sub beats all the subs in its categories hands down . I had a pioneer 126 DVC sub in my car along with two JBL GTO 0937 Speakers . I was very hesitant to get this sub installed ,however on recommendations of my dealer i got it installed and i think it was worth it . Amazing punch and bass. Very Clear sound . It gives the punch and does not make too much noise distortion . I love this sub and think is gr8 value for money . Definate buy .



Hands-on research

What's in the box?

Download owner's manual

  • One 12" woofer
  • 1 Rubber gasket (installed)
  • 8 Mounting screws
  • Manual (English/Spanish/French)
  • Online registration sheet

Product Research

Enclosure Compatibility


Polypropylene Cone: The cone is made with polypropylene, which provides durability while being lightweight and rigid. The cone is supported by a vented cone/coil coupler, which stiffens the cone for greater mechanical stability and lower distortion.

Santoprene Surround: The Santoprene surround is resistant to extremes in temperature, humidity, and exposure to sunlight for excellent long term reliability.

NOMEX Spider: The fire-retardant flat NOMEX Spider allows extended linear motion while providing highly reliable mechanical and thermal stability.

Triple-vented Kapton Voice Coil Former: Triple venting of the 4-layer Kapton Voice Coil Former, Cone/Coil Coupler and Pole Piece contribute to the high power handling and reliability of the db Series subs.

Klippel Laser Analyzed: The Polk db woofer's voice coil alignment, motor, and suspension are optimized using a state-of-the-art Klippel laser analyzer for superior cone travel linearity, resulting in a flatter response with lower distortion.

Break-In Period: Polk db subwoofers will achieve even greater performance once they are thoroughly broken-in. To break in a new db Sub, play music through it for 20 to 30 hours at moderate levels.

Enclosure Compatibility

Recommended Sealed Box Volume: Polk recommends mounting this woofer in a sealed enclosure made out of 3/4" MDF with an internal volume of 0.88 cu/ft.

Recommended Ported Box Volume: Polk recommends a ported enclosure made out of 3/4" MDF with an internal volume of 1.50 cu/ft using a 4" diameter x 10" long port.

Recommended Bandpass Box Volume: Polk recommends a bandpass enclosure made of 3/4" MDF with a total internal volume of 2.15 cu/ft. The bandpass box should have a 1.0 cu/ft sealed rear chamber and a 1.15 cu/ft ported front chamber with a 4" diameter x 12" long port.

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.

Customer Q&A