sealed vs vented subwoofers


I'd like to ask the forum what the primary differences are in sound, performance, and application of sealed powered subwoofers vs vented either bottom vented, rear, etc. B&W makes most if not all of their current line of powered subs sealed. Yet I see other manufacturers offer vented subs. What is the difference? Do the sealed subs produce a higher quality tighter controlled bass vs a more sloppy reverberating type of LFE out of the vented types? Thanks.
pdn
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I have never heard of Floyd Toole . In just what way is frequency response predictive? I will refure you to the review of the Spendor SP1 at WWW.regonaudio.com. " Many speakers look good in the anechoic test chamber or on the computer analyzer. Few of them sound good at home. And if sounding good means producing an audible facsimile of the input for a real listener in a real listening room, then most speakers do a rather poor job indeed. ". He adds: "Of course, one might hope to verify such an impression through measurement, but no one has ever been quite sure what to measure in order to evaluate performance in real living rooms. (Most of what has been passed off as "scientific" analysis has been either too crude or too biased to be of any real use or validity". Your general thesis that measurement alone is definitive of sound quality I had thought to have been abandoned years ago. Your further corollary expressed in a previous exchange that, while you had never heard the equipment I was using , logic would tell you what they sound like I find to be breathtaking in it's naïvety.
I have never heard of Floyd Toole.

Then you might enjoy reading up and learning a bit more on the engineering of audio equipment. There are University accredited courses in the physics of applied acoustics and electrical engineering. It is not all smoke,mirrors and voodoo, as some of the journalists would have everyone believing.
There are university courses on every conceivable subject including creationist geology. I prefer the work of accomplished engineers such as Martin Colloms, Ben Duncan or Malcolm Hawksford who are actually engaged in the design of audio equipment. Those who can , do; those who can't, teach has some validity here. If it were so easy to quantify the requirements for accurate sound reproduction why is it so hard to do and why does good equipment sound so different? Good designers will tell you that theory is important but it is only the starting point. An over reliance on measurement is one of the root causes of most bad sound. Hawksford is an academic [as am I] but the serious work in sound reproduction is mostly being done at the practical rather than the theoretical end.
My reference noise for reproduction in a subwoofer is not natural acoustic bass but the noise that comes from a 10ton metal stamping press at the KTP plant here in my state. Thats the real everyday authority. Who cares about the sound of real unamplified instruments anyway. The group delay of an acoustic bass or cello must be really high because they are naturally ported and are also mechanically coupled to ground very poorly just like most speakers. Tom