Sir, it is simple fact that due to the budget they have to work within, the vast majority of companies must use compromised drivers and cabinet designs. Let's even consider the Paradigm Servo 15 v.2. A very expensive over $2000 USD unit. Even it uses a very compromised driver compared to what is available. Look at the 1/2 cost of the DIY unit that ParadigmDawg now uses, employing a world class TC Sounds TC3000K motor based driver(AudioPuse AXIS). It provides complete obliteration of the Servo, due to the substantially superior motor assembly that has less power compression and far superior linearity, meaning the magnetic field and suspension of the driver act as a progressive linear device as you increase the input voltage/power to the unit. Buying the parts yourself and assembling them, you are not wasting dollars putting it into the marketing, labor, distribution and other costs involved with a pre-built item. The Infinity Kappa Perfect driver mentioned is much the same: a very linear driver(though without the extreme excursion and power handling of the AXIS driver), that within it's rated linear range, is extremely linear. Match this with a ported cabinet using a sufficient sized slot port and the result is tremendous due to that extremely linear driver. The sound quality won't change whether you use it at 85db or 110dB in your room. Something like the Klipche must use extremely compromised motor. You could easily match or even exceed the performance of the Klipsche using a $70 12" budget range Lanzar driver. Forget about comparing it to the Kappa Perfect ported build; it would take 3 or 4 of those Klipsche units to begin to match just the SPL of the Perfect, and even then, it would not likely match the sound quality, though, it might, given the much less stress on 4 drivers compared to 1, but I would not expect it to be significant. You can build a maximum quality subwoofer for about $1200 including amplification. Maximum as in there is no better ; though you need to use specific driver and cabinet design of course. You have to spend 3x or more that for a retail unit of similar quality - and even then - cost alone does not guarantee quality - but there are some very good quality retail/commercial units in the $3500-$4000 range.
For top quality SQ in ported systems, drivers include JL Audio W6v2, Infinity Kappa Perfect VQ
For top quality SQ in sealed or ported systems, drivers include JL Audio W7, TC Sounds TC3000, TC Sounds LMS5400, AudioPulse AXIS, AudioPulse UltraLMS. some SoundSplinter drivers(these are just TC Sounds drivers from TC's lower-mid range, re-branded for SoundSplinter.com retail sale).
The above are only some suggestions, there are some (bBut not many at all) other drivers that have equivalent quality.
-Chris
