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Polk Audio db840DVC
db Series 8" subwoofer with dual 4-ohm voice coils
Our take on the Polk Audio db840DVC by Crutchfield's Dominic DeVito
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
The POLK AUDIO DB840DVC is an Excellent replacement for my stock sub woofer.
What's in the Box:
- One 8" DVC woofer
- 1 Rubber gasket (installed)
- 8 Mounting screws
- Manual (English/Spanish/French)
- Online registration sheet
- 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
Polk Audio db840DVC Reviews
Average Customer Review(s):
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Features and Specs
|Impedance||2 ohms or 8 ohms|
|Surround Material||Santoprene rubber|
|Ideal Sealed Box Volume (cubic feet)||0.35|
|Ideal Ported Box Volume (cubic feet)||0.6|
|Port diameter (inches)||3|
|Port length (inches)||11|
|Dual Voice Coil||Yes|
85 dB at 1 watt
|Frequency Response||30 - 200 Hz|
|RMS Power Range (Watts)||50-180|
|Peak Power Handling (Watts)||360|
|Top Mount Depth (inches)||4|
|Bottom Mount Depth (inches)||4 3/8|
|Cutout Diameter or Length (inches)||7 1/16|
|Parts Warranty||1 Year|
|Labor Warranty||1 Year|
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.
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.
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
2 answers I see several stories on using the Crutchfield 8" subwoofer as a replacement in the '2000-2002 Chevy Suburbans/ Tahoes. This is a 4 ohm woofer. I read that my GM Chevy Suburban uses a 2 ohm sub-woofer. Can the Crutchfield be wired to work as a 2 ohm load on a factory GM amp? [ TBone Jul 01, 2016 ]
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