I am new to the whole subwoofer shopping experience, and trying to make heads or tails out of the current offerings, and am in need of some guidance from those who know more than I. I am of the opinion that a subwoofer should play down to 20 Hz. minimum, and actually should extend below that. If it cuts off at 25 Hz., or 30 Hz., I don’t want it, and in my opinion, it is not a true subwoofer. I am also of the opinion that the subwoofer should actually not be noticed so much (when playing music, anyway), but rather the lack of it should be noticed (playing music with the subwoofer engaged should sound good, true, and accurate (not boomy, or thumping), and then if the subwoofer were suddenly switched off, you should notice that it is missing). The subwoofer should not be the main, most noticeable piece in the system. It should enhance your other speakers, not overpower them. I have been running Klipsch Fortes for my main speakers for a number of years, and these are rated down to 32 Hz., (verified with test material, it rolls off SHARPLY at about 32 Hz.). I am now running the Fortes as my surround speakers with Klipsch Reference Series RF-7 speakers for the mains. These too, are rated down to 32 Hz., yet testing with the same material shows that the RF-7s actually extend down to at least 20 Hz., thus I am in need of a TRUE subwoofer (one that can extend below 20 Hz.) to get any improvement in bass extension over what I currently have. The wife unit will not permit me to play things “loud”, so I am not looking for quantity, but instead QUALITY of the bass. It should be accurate, clean (free of audible distortion and no muddiness), no overhang, or “blubbering” (when the signal stops, the woofer cone better stop), and deep (low extension below 20 Hz.). I have read the WSR Essential Subwoofer Buyer’s Guide, and while I agree with some of the things Mr. Hardesty (Dr. Boom) states, I know that MY ears are going to be the final judges, however I am hoping to help come up with a short list from recommendations here, and from reviews such as those published in magazines, or on the web. In theory, the “Feed Forward” system of operation should be best, as those items that can create errors are looked at and removed prior to the signal being fed to the woofer cone. “Servo Control” should be second best, because of the tight control they can offer to keep things clean and accurate, however they are still trying to correct an error that has already been output by the woofer into the room where it may be audible, if your ears are good/critical enough. (The Mirage BPS-210 used both technologies; however it appears to have been discontinued.) Based on the reviews I have read thus far, I am considering the following subwoofers as main candidates to give a listen to (retail prices listed). •Vandersteen V2W ($1295) •Bag End Infra 18 ($1770) •Mirage BPS-400 ($1300) •M&K MX-700 ($1399) •Paradigm Reference Servo-15 ($1500) •Velodyne HGS-12 II ($2199) The Velodyne is a pricy item, and to be honest I would prefer to go with the HGS-15 (minimum) or HGS-18, but not sure I can convince myself to spend the extra bucks for them. (I’m not sure I can convince myself to go the price of the HGS-12, unless it truly proves to be FAR superior to anything else I look at). As you can see from above, most of the subs listed are $1500 or under. The sub will be used for both movies and music (a good sub should be capable of doing either, equally well). This whole thing of being “musical” or “movie” oriented is in reality (I think), nothing more than the sub itself, putting emphasis in the area of the bass where most movie sound effects are occurring (35 Hz. and up), thus making it appear to be “better” for movies, because of a perceived emphasis (thump). I’m not stating the size of the room, because I am interested in QUALITY and not quantity (loudness), so I don’t feel the size of the room to be relevant at this time. I've heard good things about SVS but to be honest, I am not too keen on buying something "blind", which is what I would be doing if I went with SVS, or a DIY sub. To quote Billy Joel, “you can’t get the sound from a story in a magazine”. I know SVS is in Ohio (I am too), and maybe if I could audition them beforehand, I might be more inclined to be persuaded. It's just that in my mind, a sealed enclosure should be better, as there is no worry of any "port noise" to even remotely enter the sound that is being introduced into the room from the subwoofer. I am leaning in the direction of the sealed box units, due to their improved transient response, and less aggressive roll-off below their nominal cut-off frequency. Again, I’m talking theory here as expounded by Richard Hardesty, and I’m counting on knowledgeable folks from this site to set me straight, if I am mistaken. I was hoping to get some comments on the subwoofers I listed as possibilities (to reinforce their being on my list to audition, or rule them out completely), and to get some recommendations (brand, model, and price) of others I should check out. Remember, I am after QUALITY and not quantity. Most of what I have read in regards to the SVS and HSU subs seem to be more for those who want maximum output for the money, which is NOT what I am after. Again, maybe this is a misconception on my part, but most of the posts I have read and can remember for SVS, HSU, and Sunfire, have dealt with getting the highest SPL into the room, and not with getting the most accurate and deep bass output. The servo 15 was the top guy on my list not too long ago (until I read “The Essential Subwoofer Buyer’s Guide” special edition put out by WSR, which didn’t give it overall high marks in a few areas. I’ll have to be sure to audition it, as I have been told it will go well below 20, and is clean and not boomy. According to these same reviews, the output of the subwoofers I listed at 20 Hz. are: •Vandersteen V2W 94 dB (down 10 dB from 25 Hz.) •Bag End Infra 18 90 dB (down 12 dB from 25 Hz.) •Mirage BPS-400 Not stated (105 dB at 25 Hz.) •M&K MX-700 92 dB (down 8 dB from 25 Hz.) •Paradigm Reference Servo-15 96 dB (down 10 dB from 25 Hz.) •Velodyne HGS-12 90 dB (down 14 dB from 25 Hz.) The 2 highest output units (of the ones with an output listed at 20), are the Servo-15 and the Vandersteen, separated by only 2 dB. Again, remember, I am not after ultimate loudness of the bass, but rather a low, extended bass response that is clean (distortion free), not thumping or booming just for the sake of making things rattle.