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Polk Audio db840 (FREE Upgrade to 2017 Model) thumbnail image
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5 star
80%
4 star
20%
3 star
0%
2 star
0%
1 star
0%



Durability
4.8
Value
4.9
Features
4.8
Design
4.6
Usability
5

Customer Reviews

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love polk

good subs great value have never heard 4 8s sound like this before

By lance on November 9, 2010

95 found this helpful


good deal

sound and look good

By Rick on July 10, 2011

94 found this helpful


Nice little sub

I built a custom box for this sub under the floor in my hatch by the spare tire - pretty much .35 cu ft. I went with this woofer due to my positive experience with polk component speakers and it's super shallow mounting depth. It seemed to lack low lows until broken in but now I just can't say how impressed I am with an 8" woof. I have my amp bridged at 300 watt rms and the woof seems to do fine even though it is rated at 180 watts. For reference, I've got an equalizer built in to my head unit and a 40 Hz bass boost on my amp that might really be helping me dial in the sound. The lows go low enough and the high/mid bass is more pronounced. It is a quality sound not a boomy sound. That said, if you are looking to wake the neighbors from 2 blocks away, get a couple of 10's or 12's.

By jackbequick on June 25, 2010

93 found this helpful


Outstanding performance

Product was far better than the original stock woofer that it replaced, and has been solid as a rock since I installed it. Sounds great!

By Selders on May 2, 2012

91 found this helpful


Great 8

This sub is perfect for anyone wantin some added bass, its got a low price point and its reasonably shallow so it wont take up too much room. Polk is a reliable brand in my opinion also.

By Tyler on October 31, 2011

88 found this helpful


Excellent value, quality and sound

Added the Polk db840 to my golf cart sound system in conjunction with a pair of the Polk db651s. Sound from the db840 is awesome. Nice clean lows.

By Rusty on August 20, 2011

90 found this helpful


Polk audio

The Polk Audio works great like it a lot. Sounds great in my truck.

By Marco on August 12, 2011

89 found this helpful


Awesome Polk Speakers

These are great sounding speakers and they can really handle the power and still sound great. I installed these on my Polaris RZR 4 and I really do like these speakers.

By Gil on February 8, 2011

89 found this helpful


Good Buy!

6 months and counting. I love the fact that my db840's are marine certified because I have them in my Goldwing motorcycle and they have performed flawlessly. Can't wait to push these babies with the marine amp that I purchase.d from Sonic. The clear vocals and crisp sounds from these speakers should fair well with the 9 in sub that I also purchased from Sonics.

By Cope on May 1, 2012

88 found this helpful


Polk DB 804

I purchased these for some DJ speakers for the mid bass. These sound great and heave very clear sound. I have then wire in series for a 8 ohm load and am pushing 350 watts RMS and these handle it like a champ. The studio amps I am using have a cut off of 100 hz on BI-Amp mode which helps these handle more power than the rating. These are a great deal for the money and do everything I expect of them. I would definitely recommend these If you want quality sound and know what you are doing.

By usmc on July 24, 2014

84 found this helpful


great value

great speaker for the price. hard to find a direct replacement for a Yukon sub. fit great

By jesse on February 11, 2010

68 found this helpful


Great Value!

Added to stock system to extend bass response. Put in a sealed .274 cf stuffed box powered by KAC 1502. Tight, efficient bass!

By Jon on June 2, 2012

62 found this helpful


Outstanding

Great for direct replacement in 99 Navigator. Better than OEM. Very minor fit adjustment. Fantastic sound using OEM amp.

By CLicker on March 12, 2015

55 found this helpful


Great 8" Sub

I have this sub in a sealed .40 cu in box powered by a Kenwood KAS5001PS Mono amp pushing 300W RMS. I have it crossed over at 80Hz with Polk DB651's in the doors with Polk DB461's behind the seats and Polk DB1001 Tweeters all powered to max RMS power, the sound quality is incredible.

By Brian on February 23, 2015

52 found this helpful


Great boom for buck!

This speaker at its reasonable cost excelled what I expected. It delivered clear boom to make the system’s sound spectrum be full.

By Squirrel on April 9, 2018

3 found this helpful


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