What is vibration isolation for?


Where do these vibrations come from? From where I stand the earth doesn't shake too badly?! I would think that most vibrations would come via sound transmission through the air directly through the chassis of the components thus rendering the racks or other vibration isolation, uh, useless, no? (with the exception of actual thumping from walking etc)
neubilder
Anybody here tried one of them new fangled "Levitator" isolation doohickies from www.GR-Research.com/levitator.htm?

Acrylic plate floating in air based on repelling magnets...

Looks really cool but does it work????
I will be more specific - I can understand the use of isolation with mechanical things like turntables(of course), cd players, and speakers, - but people are doing this to amplifiers and pre-amps. I understand the concept of microphonics and that sort of thing, but my point is wouldn't most of the vibrations be coming via the chassis of the component itself - not the table it is standing on?
Insofar as solid state electronic components, the whole vibration thing is bogus to start with. Tubes may be microphonic and a damping ring around them can't hurt, but solid state circuitry is for all practical applications relating to reproducing music in the home not helped by vibration reducing gizmos. You are right in assuming that the music itself will cause airborne vibration to act directly on the chassis. But, hey, that does not stop real believers in spending a bundle to reduce vibration and claiming they can hear positive effects. Geez, folks in these threads keep asserting all the time that they can hear HUGE differences for passive components. Once you start making claims that everything has an effect on the quality of the sound you hear from your system, the slope is so slippery that you can very easily believe that mass loading or isolating with some form of compliant suspension will act on the circuitry. The tweakers will possibly come down hard when hearing this: amp stands et al are a crock. Good listening and don't let the buzzards bother you.
many users laughed at component isolation & vibration control until they tried it for themselves - I was one of those myself, until I tried it.

buzzard
Bob, (you don't mind if I call you Bob? Calling yourself buzzard is quite radical, I think). The users of the devices are no longer laughing because of the amounts they paid for them and the emotional attachment such an expenditure usually provokes. The manufacturers, on the other hand, are still in stitches. I know full well there is no point in getting into any kind of discussion or debate over improvements perceived on a totally individual or subjective basis. Worst yet is when a group of individuals reinforce one another's views and a cabal is born where the upshot verges on collective hysteria. I find it very different to adopt a "it can't hoit" attitude while tweaking to your heart's content; I find it another thing to assert, based solely on one's personal uncontrolled observations, that HUGE improvements occur for no logical reason. If we could actually hear electrons bobbing up and down inside cables, or the effect of vibration on solid state circuitry as believed by some, life would, indeed, be unbearable. I prefer to recognize the limits of my hearing and that of humans in general, and spend my time and limited monetary resources on software, read "music". Are present day devices used in the reproduction of music perfect? No. Is tweaking the answer? I don't think so, but, then again, if "it can't hoit", who am I to blow against the 'Agon wind. Coming back to the initial question asked: yes, indeed, airborne vibration acts on the chassis. Should we care? Nothing indicates we should, but if you fret over this the marketplace offers "solutions", how much you are willing to spend on these is entirely up to you. My bet is that one's belief in the significant improvements brought about will be in direct proportion to the amount of money spent, so strong is the belief in audiophile circles that great sound must be filtered through one's wallet.