Skip Navigation

Polk Audio db840DVC

db Series 8" subwoofer with dual 4-ohm voice coils

51 Reviews | 5 questions - 10 answers

Item # 107DB840D

This item is no longer available.

Shop all Component Subwoofers

New model available


Our take on the Polk Audio db840DVC

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.

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 db840DVC 8" subwoofer boasts a rigid polypropylene cone and durable Santoprene™ surround built to handle big power over the long haul. The dual 4-ohm voice coils allow you to wire your system to draw maximum power from your mono amp or to safely hook up multiple subs. Match a db sub to a suitable enclosure, and enjoy impressive low-frequency performance rarely found in this price range. And Polk certifies this sub for marine applications, so they're a great choice for your boat too.

Note: If you are wiring this DVC sub for lower impedance, make sure that your amp is compatible. Most car amplifiers are stable down to 2 ohms in standard mode, or 4 ohms in bridged operation.

To drive this subwoofer, we recommend a mono subwoofer amplifier that can put out between 135 and 270 watts RMS at 2 ohms. For more information please refer to our article on How to Match Subwoofers and Amplifiers.

Priced per speaker

Product Highlights:

  • 8" subwoofer with dual 4-ohm voice coils
  • polypropylene cone with Santoprene rubber surround
  • marine-certified for use in boats and convertibles
  • power range: 50-180 watts RMS (90 watts per coil)
  • peak power handling: 360 watts
  • frequency response: 30-200Hz
  • sensitivity: 85 dB
  • top-mount depth: 4"
  • sealed box volume: 0.35 cu. ft.
  • ported box volume: 0.6 cu. ft.
  • warranty: 1 year
  • Our 60-day money-back guarantee

What's in the Box:

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

The POLK AUDIO DB840DVC is an Excellent replacement for my stock sub woofer.

Steve, PA


Polk Audio db840DVC Reviews

Average Customer Review(s):

(51 Reviews)

Excellent Factory Sub Replacement

Rob D from Ft Myers, FL on 7/12/2016

2009 Hyundai Santa Fe
Crutchfield Customer Review (What's this?)

Let me start by saying, this was not a simple install. However, it's due to the fact that the factory Santa Fe Infinity Sub is in an awkward location and no replacement speaker will fit without modifications. Once you pop the rear panel back (get a helper) and remove the factory sub, you'll need to do a few things. Splice factory connectors off, use a dremel to widen the hole so the Polk will fit and test before mounting (obviously). I was able to use 2 of the factory screw holes and then had to drill a new one. Once you tested the speaker and it works, mount it. Toss the extra plastic ring away as it won't fit when you put the Infinity grill back on. You will also need to grind down the Infinity grill cover so it doesn't touch the Polk sub. DO NOT grind away the clips. Just the inner ring that protrudes. The Polk sub has a nice clean sound. Better than the factory Infinity. It works VERY well with the factory head unit. For the price, I have ZERO complaints. It's a great sub! The install was a bit of a pain but well worth it. Took me about an hour and a half with the right tools and a second person to help hold the plastic panel away from the speaker. I didn't remove as it seemed like more work than it was worth.

Pros: Great sound and range - great price

Cons: None

Polk Audio db840DVC

Steve from PA on 5/26/2016

2001 Chevrolet Tahoe
Crutchfield Customer Review (What's this?)

The POLK AUDIO DB840DVC is an Excellent replacement for my stock sub woofer.

Pros: The Polk Audio db840dvc sounds MUCH Better tha the factory sub woofer. Easy install too.

Cons: I had to sand the outer ring on the Polk sub , to make it fit in the original location. It took me about 5 minutes. Not a big deal.

Polk subwoofer

Dereck from Rockingham, NC on 5/24/2016

2001 GMC Yukon
Crutchfield Customer Review (What's this?)

Nice sound for such a small sub woofer.

Pros: Great value for the price .

Cons: None

Good replacement Sub

Tahoe2001 from Pipe creek TX on 5/23/2016

2001 Chevrolet Tahoe
Crutchfield Customer Review (What's this?)

Good easy fit in factory sub location. Use original 4 screws plus drill 4 more and wire up both coils was all it took. Factory enclosure and amp sound great!

Pros: Easy cost effective sub

Cons: Not a 100% exact fit

DB840DVC Subs

Super Subs. from Hampton, VA on 5/2/2016

2008 Pontiac G8
Crutchfield Customer Review (What's this?)

Replaced my factory with these subs, not disappointed at all.

Pros: Clear and precise sound. Great Bass

Cons: None

worked great

AaronK from El Paso, TX on 4/19/2016

Crutchfield Customer Review (What's this?)

Worked great. After i installed the speaker, My amp for my after market 12 in polk audio sub went out and i couldnt even really tell. This little sub bumps pretty good. Easy install on 2001 tahoea ls if u take the plastic ring off the speaker before installation.

Pros: Easy install. Great sound. Great price.


Polk Audio db840DVC

RN from OH on 3/21/2016

1999 Ford F-150
Crutchfield Customer Review (What's this?)

I'm on the fence with the pair that I bought. I used them to replace worn out Punch XLC's that were in a form-fitted box under the rear bench. I keep hearing a slight rattling. And I'm almost sure it's coming from the speaker centers. I've read new speakers need time to break-in so l'm trying to be patient. About 10 of 60 days in. (Read it takes about 60 hours.) I've already reset/retweaked the amp.

Pros: Decent speakers for the price.

Cons: Possibly a slight rattle.

Very good performance for a low price

Daniel from Houston on 3/15/2016

Crutchfield Customer Review (What's this?)

I bought this sub to replace a torn factory sub in a Yukon xl. The fit wasn't exact but I modified the stock box and it sounds great. This sub sounds really good with the factory set up. There is plenty of bass coming out if this sub. This is a really good price for a sub of this quality. I would definitely buy this again if I needed another 8 inch sub.

Pros: Looks great. Sounds great. Great price.

Cons: None

Polk Audio db840DVC

Eddie from Jensen Beach, Fl on 2/24/2016

Crutchfield Customer Review (What's this?)




2001 Tahoe replacement

Brian from easthampton, MA on 2/8/2016

Crutchfield Customer Review (What's this?)

I was hesitant to get this after several reviews stated it would not fit my Tahoe yet Crutchfield said it would but would need to drill new mounting holes. Crutchfield was correct. If you remove the rubber gasket/ring it fits the factory sub box. You will/should use new mounting screws as the factory ones provided by Polk are too long in this instance. I used silicone caulk in place of the gasket when I mounted it to eliminate any rattling once I buttoned up the trim.

Pros: Bass is strong. It is only 8" so my expectations were not high and the Polk is an improvement over the OEM sub. At $60 you can't really go wrong.

Cons: None

Polk sub woofer

Daniel from Pleasant plain, oh on 1/22/2016

Crutchfield Customer Review (What's this?)

Sounds good, not a plug and play install as I was told.

Pros: Sounds great

Cons: Fabrication to install in factory box.

Excellent Speaker - Not so great fit

bunhead from Arizona on 12/28/2015

Crutchfield Customer Review (What's this?)

I bought this to replace the blown factory subwoofer in my 2002 Tahoe. Crutchfield said it would fit but it didn't. The speaker was just slightly too large to fit into the box. I just drilled and screwed it on over the insert. The problem now is it works so well it vibrates the plastic car liner that covers it. Sounds terrible. I'm going to need to cut a hole in the liner and try to cover the speaker with a grille. Unfortunately there isn't a grille made for this speaker and, at this point, I'm not sure what to do. I may end up just disconnecting it.

Pros: Seems like a good quality woofer with lots of base

Cons: Didn't fit into my Tahoe and creates some very bad sounding booming and vibration

Crutchfield response on 12/30/2015 We forwarded this review to our Technical Support team for follow-up. Lifetime tech support comes with every Crutchfield purchase.

Freakin SWEET

Chrism from South Carolina on 12/10/2015

Crutchfield Customer Review (What's this?)

This 8 inch sub is way better than I thought I was getting. It hits pretty dang hard

Pros: The sound that comes out of the little sub is awesome

Cons: None


Scott K from Jacksonville, Fl on 10/18/2015

Crutchfield Customer Review (What's this?)

Very I can crank my tunes without any break up!



They're eights

Rouge6 from Independence va on 10/12/2015

Crutchfield Customer Review (What's this?)

What can I say I've owned several kicker and fosgate products... Tens 12s and 8s... I have this pair on a kicker 500.1xi amp wired up 8 each and dropped to four on the amp the set up is fair and only that they are punch tight bass but tend to muffle... Again these are 8s... They are fine for a truck with limited space. I do prefer my stage 3 punch tens over these but they are also on a 1000 punch amp.... Don't expect loud bass just a replacement bass from the lack of bass from after market

Pros: Dvc and for those who tend to forget how to wire dvc they instruction book runs you through it allall... Also they are marine also great for a truck

Cons: The rms tends to be a little weak even the max is a bit low... They aren't really worth the price but hey... If they ever go on sale I say grab them they aren't the best 8s but they do the job

Polk audio sub with tahoe

Bob from Kentucky on 7/17/2015

Crutchfield Customer Review (What's this?)

Huge difference from factory sub in 2002 tahoe.



Polk Audio car speakers are fantastic

Buddy G from Castle Rock, CO on 6/25/2015

Crutchfield Customer Review (What's this?)

Installed Polk Audio dB 840DVC crossovers, tweeters and subwoofers with a Kenwood Excelon KDC-X998 receiver in my Lexus ES300. The sound quality is incredible, I love hearing the separate treble, midrange, and bass notes so clearly. I highly recommend these speakers for great sound quality. Driving now is actually fun.

Pros: Very clear sound for any type of music. It's great to hear so many different musical instruments like, cymbals, drums, wind and string instruments and other things that were there before but all blend together with poor quality factory speakers.

Cons: None

Polk sub

Michael from California on 5/15/2015

Crutchfield Customer Review (What's this?)

Great sounding sub, polk never fails to impress, Crutchfield comes through again great customer service

Pros: Easy to install even with dual voice coils

Cons: No cons with polk sub or Crutchfield

Awesome factory replacement

g from Georgia on 5/4/2015

Crutchfield Customer Review (What's this?)

Replaced a factory sub with this unit in a Grand Caravan. Shocked at the sound this little thing can put out combined with the inexpensive sound ordnance M-1350.



Polk dp840DVC

Todd from Dallas, TX on 4/30/2015

Crutchfield Customer Review (What's this?)

WOW! Hard do believe this was under 70 bucks! Replaced factory sub in 2002 Z71 Tahoe and it hits & sounds great. I had to trim so of the rubber off around the edge and make a cross over wire to make it a 2 voice coil. To save so trouble you might wanna order this so your not running to walmart at 11pm at night : ). I'm not a young kid anymore and don't know a lot about hooking up electronics in cars. However when I called at 10pm someone answered their hotline and helped me figure out how to make my own crossover. Big thanks to the Morgan (ext 3234) and the guy who talked to me for 30 mins 10 at night. Would highly recommend for someone that's doing themselves and wants a little boom in their sound.

Pros: Great value for the bang/boom

Cons: Didn't come with wires to make it a 2 voice instead of a 4.

Polk Audio db840DVC

Anonymous from Fort Worth, TX on 4/12/2015

Crutchfield Customer Review (What's this?)

Product was definitely affordable , quality is ok. Not great.

Pros: Cost, installation easy to replace

Cons: Adapter wiring not perfect fit, had to adjust when hooking up positive and negative . 8 screws for sub into box, too many.


emergency vehicle installer from Tracy,ca on 4/5/2015

Crutchfield Customer Review (What's this?)

Great fit with no modification needed. Used this to replace the factory sub in a Ford expedition. Great sound even with stock Amp. Great value.

Pros: Fit factory enclosure in expedition with no modification, great price, great sound.

Cons: You have to wait a day or two to get it.

Polk db840

Drew from Hawaii on 3/13/2015

Have the svc version in a sound ordanance .38 sealed box. Feeding it 300 watts rms and it takes it like a champ. Rattles the car more than I expected.

Pros: Handles double the rated rms without sweating.

Cons: Connectors are cheap.

2002 GMC Yukon

Anonymous from Murfreesboro, TN on 1/10/2015

Crutchfield Customer Review (What's this?)

Replaced the stock sub in an '02 Yukon nicely.



Great value for the money

Tim from Phoenix, AZ on 1/1/2015

Crutchfield Customer Review (What's this?)

Installed this last year for my son in his 2001 GMC Yukon XL. Like others, it fits but with minor modification to mounting rim. I took the cardboard mounting rim off the old subwoofer and used it as a spacer for this one; used tape to seal out air leaks. Sounded OK but that was with factory amp. This year's xmas present was a new Kenwood X598 stereo (see separate review). Huge difference. Don't hesitate to change out all the factory speakers and factory garbage stereo; you will be amazed!

Pros: Value for money spent, Crutchfield instructions, sound quality, build quality

Cons: Installation modification (minor)

Polk Audio db840DVC

Jeff from West Mifflin Pa. on 10/8/2014

Crutchfield Customer Review (What's this?)

Subwoofer sounds great


Cons: had to make some modifications to fit the 2002 Chevy Tahoes box, no big deal

8" Sub for 03 Expedition

David from yuma, Az on 10/5/2014

Crutchfield Customer Review (What's this?)

I've had this installed in my 03 expedition for a week now and I have no complaints. I used an aftermarket amp attached to it and it sounds amazing. Definitely an improvement from the stock set up. It doesn't rattle the expedition, but it definitely gives it a nice deep low sound that the door speakers wouldn't be able to produce themselves. I did have to use heat gun to help push out the back the plastic stock subwoofer enclosure and drill my own holes, but besides that the setup was relatively easy.

Pros: Sounds great

Cons: Had to alter stock expedition enclosure

Polk Audio db840DVC

Anonymous from altoona iowa on 10/3/2014

Crutchfield Customer Review (What's this?)

This sub works great.



Nice Subwoofer Speaker!

Janet from Chandler, AZ on 9/27/2014

Crutchfield Customer Review (What's this?)

We bought it to replace the 8" speaker in our Advent 8" Powered Subwoofer for our home theatre and it works great! Because of the dual voice 4 ohm coils, we were able to wire the subwoofer in series to the 8 ohms we needed for the Advent unit. It fit into our unit like it was made for it! I couldn't believe it when the screw holes lined up! I'm planing to buy another one and install it in my car. Shallow depth makes it great in a little car.

Pros: Inexpensive price, great sound, dual coils for varied installation.

Cons: It's not free! Ha Ha! No cons!

Good speaker

Nice speaker from NYC on 9/6/2014

Crutchfield Customer Review (What's this?)

This is a great sounding speaker. I am using it in a Pioneer box made for a 10 inch speaker with an adapter I made, and it hits hard.

Pros: Has 2 voice coils that are each 4 ohm. This means that when you wire it parallel you get a 2 ohm load, which is perfect for most amplifiers.

Cons: None I know of

Great Speaker

DennisM from Lincoln, NE on 8/22/2014

Crutchfield Customer Review (What's this?)

This is a great speaker with excellent versatility. The dual voice coil makes it easy to connect in stereo at 4 ohms or mono at 2 ohms. The sound quality is great. The only problem I ran into was the rubber gasket around the out side of the speaker is slightly wider than the speaker itself, and had to be trimmed to fit in the factory sub enclosure in my Tahoe. The space tolerance is very tight in the box.

Pros: Cheap. Sounds Good. Versatile installation.

Cons: None.

great look

Anonymous from new brunswick nj 08901 on 7/22/2014

Crutchfield Customer Review (What's this?)

Sounds ok to higer volumen low volume sounds great look nice design its cool but need to improbe bouncin sound whit the doom

Pros: Looks cool fits on the original box on my truck no need change amplifier i use same conections dame box just need litle woork

Cons: Litle distortion to hig volum need to improbe diameter to adjust original equipment

Pleasantly surprised.

Dan from Kenai, ak on 7/4/2014

Crutchfield Customer Review (What's this?)

Purchased this sub and some small enclosures for my 2000 Chevy pickup. With the limited space under and behind the rear seats I decided to use an 8" sub, I wasn't expecting much. After wiring and test fitting the enclosures I was pleased at how little room I lost, but still thought with the smaller size my bass wouldn't be very powerful. However after powering up the first time and only using half or so volume I was blown away! I don't expect to win any competitions with only 100 watts but I'm very pleased with my system. I'm planning on buying another to fill the other enclosure and can't wait to see how that sounds. Crutchfield has once again helped me find exactly what I was looking for and at a great value! Due to my budget for this project I was expecting to have to settle for okay bass instead I have amazing bass, and I can say I've got a Polk sub.

Pros: Several wiring options to allow for multiple drivers without increasing or decreasing impedance. Compact size for easy placement. Quality.

Cons: None so far.

Polk Audio db840DVC

Wilson from Columbia, SC on 5/10/2014

Crutchfield Customer Review (What's this?)

Sounds Great

Pros: Fit's My 01 Suburban

Cons: None

Polk Dual Voice coil 840

JC from Livoina Mi on 4/26/2014

Crutchfield Customer Review (What's this?)

For it's size it pack a punch, great value.

Pros: The Dual Voice coils allow for more configuration options.


These 8" subwoofers produce bass like high end 12" subs.

Kelvin Heater from Orange California on 3/21/2014

Crutchfield Customer Review (What's this?)

With slight modifications this speaker fit in my factory sub location and it sounds great. I have a five channel Alpine V12 with a Kenwood head unit, and i don't have to turn up the volume to get a head to toe massage. When i crank the music, it sounds like I have 2 12"s that are competition quality. My Suburban sound like an Imax Theater when i play video games or movies and my family loves it. I didn't even lose any grocery/ seating/ or storage space, you can't even tell that I have a pounding system unless you know about it (my poor neighbors).

Pros: Awesome punch for the price, clear as heck, and a great price.

Cons: I only had to make minor modifications to put this in my factory suburban enclosure. Otherwise nothing bad to say, at all.

Great price on a great sub

The Cat from Mi on 10/1/2013

Crutchfield Customer Review (What's this?)

I replaced the stock sub in my Yukon and only had to do 2 quick mods to get it to work. I installed it in under 45 minutes and couldn't be happier with the improved sound and clarity. I would recommend this for anyone looking for a quality sub for a great price.

Pros: Inexpensive, great sound, built well

Cons: Couldn't use Polk supplied gasket to seal speaker to factory box. I had to use a strip of foam tape.

Polk Audio db840DVC

Jon from Fayetteville, NC on 8/30/2013

Crutchfield Customer Review (What's this?)

Installed the Polk Audio db840DVC in my 2001 Chevy Tahoe. Had to modify slightly to drop down to 2 ohms, which was easy to do. Fit easily into the existing box in the rear cargo area of the vehicle. Excellent sound!

Pros: Easy to install and excellent sound.

Cons: Had to wire the voice coils in parallel in order to drop down to 2 ohms.

polk audio db840dvc

john from baltimore, md] on 8/24/2013

Crutchfield Customer Review (What's this?)

sub woofer works fine in my Gmc Yukon ,I see price has dropped 20.00 bucks

Pros: fit perfect and works fine ,gave perfect directions on how to remove panels from Yukon to get to sub woofer to replace it

Cons: none

Didnt Fit - Polk Audio db840DVC

JK from Frisco Tx on 8/5/2013

Crutchfield Customer Review (What's this?)

I would have loved to use this Sub - but this was the first time that something they told me would fit didnt. I have a 2001 Suburban with a factory Sub in the rear and it requires a shallow mount Sub. This Sub was 4" deep. I had it wired and ready to install - because they recommendations had always worked before. This is 1 case where I guess their information for the Suburban isnt always correct. I was disappointed because the price etc was just what I wanted.

Pros: Nice Sub - I've liked Polk in the past - rating is based on if I could have used it

Cons: didnt fit the application as promised

Great replacement sub for stock 2001 Tahoe/Yukon

JohnK from Saint Louis, MO on 7/25/2013

Crutchfield Customer Review (What's this?)

Have a 2001 Chevy Tahoe that had an old, dry rotted, 8" subwoofer as part of the non-Bose system. This model Polk sub was a recommendation by Crutchfield's customer service. Wow! Very pleasantly surprised. The stock GM amp does well with this sub wired down to 2 ohms. I had to omit the rubber surround ring to get the sub to fit in the factory box. A few holes quickly drilled and the job was complete in short order....maybe 45 minutes, tops.

Pros: Great sound, excellent value.

Cons: Can't use rubber surround ring in my application....but that's the only downside I see.


Rex from Ovid, NY on 4/28/2013

Crutchfield Customer Review (What's this?)

I needed some base in my boat, I have used Polk Audio before and find their sound quality to be second to none.I am not disappointed in this one either. I put one sub in a .5 cubic foot box connected to an older 250 watt, with alow pass filter, bridgeable Jensen amp that I had laying around. It sounds awesome. Super tight and rich. The only thing disappointing is Crutchfields specs on the MM series. They look the same but on Polk Audio's site the MM's are much more efficient. I would have sprung for the MM's had I discovered this before purchase. But this sub is still AWESOME!!!

Pros: Tight,Well made,good looking

Cons: None

Finally some Bass!

Mike O. from Mount Vernon. WA on 4/26/2013

Crutchfield Customer Review (What's this?)

Just installed the Polk db840DVC in my 2001 BMW Z3 Roadster and, WOW, what a difference! I finally have some Bass I can actually feel and hear. My goal was to have more bass without losing trunk space or leg room in the cabin. I replaced the stock 5.25" subwoofer and had to do some custom modifications to make this 8" driver fit in the factory location but, it turned out great! I have replaced the stock head unit with a JVC Arsenal HD receiver that has many variable settings for the bass response and I have found that using the 60hz bass boost setting really makes this driver hit hard. I am still using the stock power amps so, I think it will sound even better once I replace them. That will be the next upgrade. This Polk gives great bass at a fantastic value. I bought mine from the scratch and dent sale but it looks brand new! I had read many reviews about the lack of bass in the Z3 due to it being a convertible but after getting the Polk and with a little work, I have BASS!!!

Pros: Awesome sound. Nice tight, deep bass. Looks great too. Excellent value.

Cons: Non!

Great Product

Matt from Arkansas on 12/17/2012

Crutchfield Customer Review (What's this?)

This sub is great for replacing a GM sub, it can be wired down to 2 ohms

Pros: Perfect replacement for GM sub

Cons: none

Totaly Surprised !!!

Robert from Sarasota FL on 5/18/2012

I have been building custom car audio systems for 20 yrs now. I got into car audio when I was 14 and at 34 I am still hooked. I bought an 07 Silverado shortbed reg cab and space is extemely minimal. I built 2 wedges for behind the seat with a sealed down fire design and HOLY MOLY. I can not believe the sound of these little woofers. One of my neighbors came over to check out the awesome sound coming from my truck and said "Wow how did you fit 12s back there ? Are those low profile subs ? " When I showed him he was blown away. I am blown away !!! I kid you not in the right box these subs are un beatable in sound quality. Crystal clear punch and low end bass notes with out a hick up. I am Running a Kenwood DDX616 6.1 touch screen and a Kenwood KAC-7202 for power to these Polks. And just as a reference to my ear for sound I run a single Infinity Kappa Perfect M3D 12 in my CTS that knocks things of shelves in my nieghbors apartments !

Pros: Were do I begin !!!

Cons: None !

Polk Audio db840DVC

Anonymous from evanston ill. on 6/15/2011

Crutchfield Customer Review (What's this?)

very good sub now need 2 upgrade speakers



Awesome speaker

Dave S. from Oberlin, OH on 5/14/2011

Crutchfield Customer Review (What's this?)

I bought this sub to replace the blown original in my Advent powered subwoofer in my home theater. the spec's were comparable and I hoped it would workout ok. The sound out of this little 8" is amazing. The bass is far deeper, crisper and tighter than it ever was with the original. The best part is that it doesn't overpower the rest of the system while watching a movie. It fit in perfectly with my old Polk speakers and new Denon AVR 1911 receiver. Money well spent.



Replacement Woofer for A Logitech Z-680 System

BigDave from Jersey City, NJ on 2/12/2011

Crutchfield Customer Review (What's this?)

Needed an 8 inch, 8 ohm subwoofer to replace in my Logitech system. This one fit perfectly. No cutting or drilling necessary. Just be sure to remove the rubber gasket. Doesn't have as much boom as the original woofer but that is okay because the original one overpowered the rest of the system anyway. This one gives the system a nice balance now. Great product. Should sound nice in the car if you like your bass nice and tight and not boomy.



excellent speaker

lino from duluth, ga on 10/13/2010

Crutchfield Customer Review (What's this?)

excellent sound, and best of all excellent price and advise from marie



BOOM... boom

BrianC811 from Huntsville, AL on 9/24/2008

Crutchfield Customer Review (What's this?)

I redid my 98 Expedition in all Polk speakers and included this sub. Overall for the price, I think that it is a great bargain. It's got good sound to it, volume is decent, but it you are looking for large amounts of bass, I don't think that this is the best sub. If you are wanting something that is great to use to watch movies and goes well with most types of music while not too over powering, I don't think that you can go wrong with this mid-range sub.



Polk Audio db840DVC

Rodger from Haleiwa, HI on 9/19/2008

Crutchfield Customer Review (What's this?)

Outstanding value. I put together a mid-level system for an older mini-truck with an RF 450 Punch for the solitary amp. I am running this speaker bridged on the rear out put of the RF amp and could not imagine needing any more belt from a sub-woofer. Great buy, excellent support.




Hands-on research

Product Research

Enclosure Compatibility


Dual 4-ohm Voice Coils: This woofer features dual 4-ohm voice coils that offer wiring flexibility. When the voice coils are wired in parallel the woofer presents a 2-ohm load, when wired in series the woofer presents an 8-ohm load.

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 0.35 cu/ft.

Recommended Ported Box Volume: Polk recommends a ported enclosure made out of 3/4" MDF with an internal volume of 0.60 cu/ft using a 3" diameter x 11" long port.

Recommended Bandpass Box Volume: Polk recommends a bandpass enclosure made of 3/4" MDF with a total internal volume of 0.90 cu/ft. The bandpass box should have a 0.40 cu/ft sealed rear chamber and a 0.50 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.

Q & A

Customer Q&A

Crutchfield asked  
Why did you buy this?

Seemed reasonable. [ Craig  Jun 19, 2016 ]
I needed the mounting holes to match up with my factory woofers in my Pontiac G8 GXP (most nominally 8" woofers would not match, where I could even find the information) and Polk Audio is a brand I have had good experiences with in the past. I did an online chat with Paul, and after he had collected all my measurements of the factory wooofers he recommended these. [ Richard  Jun 17, 2016 ]
Good product for the right price. [ Brian  Jun 05, 2016 ]
To replace a defective subwoofer [ RON  May 20, 2016 ]
GM no longer carries the sub woofer for my Tahoe. So CRUTCHFIELD had the one to replace it. It"s probably a much better SUB than the factory speaker. [ Steve  May 13, 2016 ]
picked this speaker with the help of one of your online staff to match up with my current amp [ Tim  May 08, 2016 ]
I have really enjoyed my Polk Audio for the last 3 1/2 years; so I just decided to make it a complete matching set of speakers in my new car. And when I saw the $20 savings on the sub and it was your top seller, it was a no-brainer! [ Steven  Apr 02, 2016 ]
Replacement for the factory sub in a 2000 Yukon. Closest matching recommended enclosure volume of .36cft factory enclosure, while maintaining the available mounting depth. Recommended at .35. [ Kaylia  Feb 15, 2016 ]
I have Polk marine speakers from Crutchfield throughout my jeep already and it's finally time to replace the last thing, the sub. I wanted it all to match and this is the closest I could figure. [ Warren  Feb 02, 2016 ]
dual coils, high power capability and small size that fits in a box in the back of the Jeep Cherokee. [ Curtis  Jan 29, 2016 ]
Wanted to add some depth to the audio system in my car [ Johnathan  Jan 24, 2016 ]
Came highly recommended by Crutchfield staff and other LS430 owners. [ Christopher  Jan 16, 2016 ]
Not sure what this is but if Cruthfield recommends it, you probly can't live without it! Update, this is the 8 inch sub or better known as the loose hardware sniffer outer! She dumps! [ Kevin  Dec 22, 2015 ]
All based on advisor recommendations [ James  Dec 16, 2015 ]
Needed a woofer for my daughters car to replace the stock speaker that is blown. [ MICHAEL  Dec 15, 2015 ]

5 questions already asked

Yes you can, you wire the two voice coils on the subwoofer in parallel to get a two ohm load. This Polk subwoofer sounds good for us with the GM amp [ Michael  Jul 05, 2016 ]
Yes, the sub has the options to bridge the dual voice coils together for 2 ohm applications. [ Marvin  Jul 05, 2016 ]
The best way to wire you DVC subwoofer to a 2 channel amp is in bridged mode. Most 2 channel amps can be bridged, meaning you'll use the positive output of one channel and the negative output of the second channel. You'll have to follow the instructions that came with your amp to determine which speaker outputs to use for bridged mode. Also, rarely can a 2 channel amp in bridged mode handle less than a 4 ohm load. That means you MUST wire the voice coils of your DVC subwoofer in series. The negative input of one voice coil must be connected to the positive input of the second voice coil. The remaining positive and negative inputs will then be connected to your amp. [ Roman  Jun 24, 2016 ]
yes that is correct [ Kirk  Jun 24, 2016 ]
We have a 2002 suburban with the factory sub. When we purchased the suburban I took it home and noticed the sub surround was completely crumbling apart. This fits the hole and works really well. I did notice the surround rubs the plastic trim cover in front but it has not really affected the performance. Sounds great compared to the previous dead sub. [ Dan  May 02, 2016 ]
worked great in my 01 [ Lance  May 02, 2016 ]
I installed this in my 2002 Tahoe and it worked well with the stock amp. You may have a Bose system in your Yukon and it should still work for you. Hope this helps. [ ROBERT  May 02, 2016 ]
I put one in my 02 tahoe it works well with the factory amp [ kevin  May 02, 2016 ]
It will be a good match for the Rockford Fosgate Prime R250-1. You will want to wire the voice coils in parallel, and you will need to set the gain down slightly on the amp. [ Jeff  Feb 01, 2016 ]  Staff
For details on fit or installation please contact an Advisor by phone (1-800-324-9695) or online chat. They will be able to pull up your vehicle and give you the details on if this will fit and what you will need for an installation in your vehicle. [ Krissy  May 05, 2014 ]  Staff