@mijostyn --
"... I did not say there were not other ways. They are generally a lot more expensive, not any better sounding and have limited functionality vs a full fledged computer. My system doubles as a theater. I can also stream videos and movies as well as any audio service. I can record records to the hard drive and AB various versions of ...you name it. IMHO music servers are an insane waste of money. It is like comparing the pricing of commercial vs consumer audio equipment. Hint, professionals are not as easily conned."
Can’t really say what you’re after here, but I’ll bite: pro digital output PCIe sound cards from RME, Lynx and Marian, not least Word clocked, to my ears are the easy and generally cheaper equivalent to USB or USB to S/PDIF offerings - the latter of which have been the hot cakes in computer audiophilia for several years now, and are a true PITA to be brought to their fuller potential (go figure). No indeed, pro’s aren’t easily conned; naturally they’re not going for the latter option.
And regarding PC’s/music servers: mine IS a fully fledged full ATX-sized DIY computer with care taken into a low ripple and powerful PSU, mobo choice, processor, RAM, etc. and overall implementation. A lot more could be done here, but it’s a balancing act with other areas that need attention as well.
"One last thing. The problem with ears is that they are connected to a brain and when brains are concerned all bets are off. Example. Have a dispute with your wife then go mow down 50 people with an SUV. Sometimes brains really s-ck."
Getting down to brass tacks: if one’s ears deems it’s worth going for, it is. If not.. And let me bring it to you - peoples brains seem to f*ck up their decision making perfectly well without the aid of hearing. Often it’s all about the proper narrative, and if it wasn’t as much about spousal-imposed restrictions, aesthetics, conjecture, prejudice, convention, snobbery etc. and a little more about what hits the ears only, well, that’d be something to cherish, I find.
"The material a surround it made from really does not matter. It is the design of the surround given the drivers intended use. Certain designs work best with certain materials. Subwoofers need a large X max and a long throw, low compliance suspension requiring large dual spiders and butyl surrounds. Foam surrounds are a poor choice for subwoofer drivers as the stress causes even the good foam to disintegrate. 25 years is not good enough. A suspension should never fail."
That a suspension material doesn’t fail for several decades is just a convenience. Foam surrounds allow for application in designs that otherwise wouldn’t be properly implemented, so yes you’re right; it’s what the design dictates. Subwoofers don’t necessarily need long throw drivers with butyl surrounds though, but more on that below.
"... unless you are using an insanely large driver (21") you are not going very low at all. In order to move the amount of air required to produce a 20 Hz note a 12 or 15" driver has to move quite a distance especially at volume. Even at moderate levels the excursions would be plainly noticeable. If they are not then your woofers are not doing anything below 40 Hz. It is simple physics and it does not matter what type of enclosure you are using. Distortion does increase with excursion distance after a point. Modern subwoofer drivers can easily do 1 cm excursions without distortion, some up to 2 cm. Down below 40 Hz it is not what you hear that counts. It is what you feel. A 20 Hz sine wave played at just 75 dB causes my entire house to rattle. I have four 12" subwoofers in a 16 foot wide room and you can see the excursions across the room."
You make absolutes from a local context - your own. No, a 12" or 15" driver doesn’t have to jump wildly about to make to some rumbling at 20Hz, but you’re right that they will in a sealed enclosure with max. excursion at the tune - that’s also physics. I can tell you for sure that a 15" B&C pro driver with accordion cloth surround and +/- 9mm Xmax in a pair of tapped horns like I’m using only vibrates at levels down to 20-ish Hz that shakes the air quite violently, because the horn enclosure and the specific loading of the driver does the heavy lifting with excursion minima at the tune. They’ll each do ~120dB’s at the LP @ 20-25Hz and stay within the B&C’s Xmax limits - that’s a damn fact. Actually, add a few dB’s because they’re corner loaded.
Where it does get hairy is sub 20Hz into the infrasonics. This is where you need a couple of big a** drivers to produce proper pressure to make these ultra low frequencies matter as something that reverberates your whole body. To some a subwoofer (for the term to be strict) should cover down to 10Hz, but mostly that’s fruitless unless you have the right floor and room construction and über displacement capacity plus -wattages at hand. Horns would be quite big indeed to do the honors down that low, but you’d get away with using fewer drivers.