Polk Audio db840 8-Inch Single Voice Coil Subwoofer

This review needs to be updated it’s not a Polk DB840 subwoofer anymore reading from old reviews. It’s the Alphasonik HSW208. Let me be the first to update the reviews. Hooked this up to my receiver without a box & already it sounds impressive produces clean accurate bass & sounds like it can get low in the right box. It vibrates my floor already. I am going to use it as a stock woofer replacement in my Acura RL with the Bose system & see how well it does as a trunk mounted woofer. Depending how well it does I may build a box for it if needed. Stay tuned for an update if you are interested in this woofer. It’s well built, pretty heavy, booklet is very informative & professional. Packaging was very nice & came with a free Alphasonik bag inside. This is the first product I have bought from them. Update: Finally got around to installing it in a box that’s smaller then specs but this little 8 sounds clean it can pick up the lows & slams on the highs for an 8. Box I got was smaller & woofer is breaking in sounds better the more I play it. 3 of these paired together In the right box would be a nice sq build that holds its own in the world of 8s

El producto no es marino, y ponen en la descripción que es marino certificado

So, I blew out my Mitsubishi Montero's(With Infinity Sound) stock sub-woofer and because I could neither find what the model of the previous stock sub was, or locate any subs made for the system I decided to take a gamble on this subwoofer. After tearing apart the car to get the the subwoofer we just wired this sub directly where the old one was, same Infinity amp and all. Not that anyone else has a Mitsubishi Montero, but if you do. and you have the Infinity Sound system, this sub will work as a replacement sub. It's only 4 inches deep which is short enough to fit in the hole and it is wide enough where all you need to do is drill new holes in the metal to get it fastened in. The sound provided by this amp is superb, I don't really crank up my sound system so I can't tell you what it does at ear splitting decibels, all I can say is that with the system cranked up enough to hear it fully going down the road at 55 mph with the windows open, this sub packs a distinct punch. I'm sure you could get a lot more out of it if you saddled it with a higher power amp, not what I was looking for though. The sound quality from this sub is something you won't find in the cheaper offerings out there, it's a very clean. No rattle bass, what you'd expect from an 8 inch sub. It's really too bad that I've got a grate over my sub because this baby actually looks pretty cool. It's just classy. Hope it helps!

I bought this to put in a 2011 Hyundai Genesis Coupe. Mine did not have the good stereo, so I also bought an amp and a line output converter to connect the speaker wires to so that I can have RCA outputs. I was skeptical at first because even Polk said it needed to be in a box. I bolted it to the rear deck in that 8 inch opening, hooked it all up and put in some of my kids music. Okay, it won't win any prizes set up like that, but it sounded really good. The bass was deep and loud. The trunk works pretty good as a box too. The only problems I ran into was that the bass would move the whole rear deck up and down, and also the fear of blowing out the back window while listening to Beastie Boys, Paul Revere. No noticeable distortion while cranked high on a Kenwood eXcelon Reference Fit 5-Channel Digital Power Amplifier (80 Watts (RMS) x 4 / 350 Watts (RMS) x 1). Putting it in a .5 cubic foot box would definitely tighten up the bass, but it performs very good in my set-up too. Dan

This sub is a very nice upgrade over the standard subwoofer that comes installed in the LSi15 floor standing loudspeakers. Although the stock sub uses the same aerated cone material of the excellent 5.25" inch drivers in the speakers, in 8" guise it is hollow, thin, and poorly controlled when compared to this sub with roughly the same sensitivity. The Lsi15's are worth whatever you pay for them (suggested MSRP or down) but this sub being swapped in the factory unit's place fixes the only nit I had with them. Overall this is a wonderfully musical sub that produces tight response and silky experience with music and movies alike. Furthermore, it sounds wonderful and proportionately correct quiet or "melt my high frequency crossover section" (i've done it before) loud. For 150% of the Amazon price ($46 at the time of writing) I just don't see how you could go wrong with this in a car application unless, as others have mentioned, you are going for sheer SPL. The preceding was a disclaimer for those who might not understand the surface area factor. They get plenty loud enough sans distortion' loud enough to be played distortion free continuously to have the rest of your audio come out at level where OSHA would require hearing protection for exposure time. Quality wise this, paired with a reasonable ported box of appropriate size (my home stereo application is ported so I can't speak to the sealed box quality) should be a front runner on the price and/or performance list of everyone to try.