Looking for a musical subwoofer @ $500>


Had some thoughts, but figured I would ask here as I was given some great advice for my previous amp/preamp questions: https://forum.audiogon.com/discussions/amp-preamp-or-avr-for-home-stereo-and-entertainment

System sounds great btw! Parasound A23, Integra 80.3, KEF Carina II's, Technics turn table, and a Blu Ray Player. 

Anyhoo - I could use some more bass. The KEFs get down to 55hz but a lot of my music goes lower and I don't want to compromise... to a point. 

Looking for a sub capable up 25-30hz on the low end with anywhere from 8-12" driver for less that $500. I came across the Klipsch R-12SW and the reviews were stellar, especially for the price. Want this for music more than Home Theater, but both would be nice. I've even read that the Pioneer SW-8 or 10 is a fine unit for the price. 
I know of names like Sunfire and Velodyne, but I wonder if it's worth buying into those companies if I can only afford the lower end products.

Also, my guess is that buying a used subwoofer is like buying a used race car... expect it to be driven, hard. 

Thanks in advance!
128x128samgoldenberg
Don't know the starting prices for Hsu and Outlaw, but they are two companies, (along with SVS), that are specialists in high quality budget subwoofers.
I believe SVS has a generous trial program (45 days in home with free shipping BOTH WAYS!). I'm not familiar with the Hsu or Outlaw in home trial.
 SVS also have a nice tool, (Merlin), on their website to match your speakers to their subs, it is fairly exhaustive in terms of main speaker listings, but I don't think your speakers are on the list. I would give them a call at their 800 number and get a staff recommendation. The online tool not only acoustically matches several sub choices to your main speakers, but they typically are a good match "budget wise". My take on SVS is they don't try to oversell. Another option is to try a couple of Pioneers, or Dayton subs (Parts Express), as two subs should provide 
Whoops sent my response off before it was finished by mistake.
Two subs may help achieve a smoother in room response and more output. I would be surprised if the two "cheaper" sub option would be as well built as the low end SVS or HSU subs. I would also compare warranties, vendor knowledge/advice and tech support.
So I've boiled it down to HSU VTF-2 MK5, SVS SB1000, Outlaw UltraX 12. They range from $500-650. I'm going to call SVS in a moment, but in all likelihood they will want to sell me an SVS sub, so, with that in mind, any final thoughts? 

Appreciate all the help.
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Hsu - I have the VTF1 MK-III (2 of them). I find them quite musical with my Maggies. They are real easy to integrate.