Speakers in general
The other end of the spectrum from the "open-air" subs is the "sealed" speakers. Try it with your sub. Just put your hand over the hole (the port) when something is playing with a bit of bass, & seal it with the palm of your hand. You'll hear the sound change - it will be quieter, but perhaps a little less distorted ("tighter").
Sealed boxes allow the speaker's movement to be "cushioned", but it means that you need a bigger amp to get the cone to move in & out enough to get the same noise level. Thus, (computer speakers in particular) speakers sometimes are made to be ported, so that the amp can be smaller (which is cheaper), you get more sound (sort-of), & you can be a little more relaxed in the design of the box itself. However, some individual speakers (the cone/electromagnet bit, not the whole box) are better in certain circumstances, so it all depends on what is being thrown together. This explains the Altec/Creative dilemma - the speaker is probably a better one in the altech, but it is more inclined towards being sealed, but it was probably more expensive, because it probably has a bigger amp (or, creative could have done the usual big-brand thing & massiely overpriced it. Microsoft, Dell, Sony anyone??)
As for "touching sound waves", you kinda are - you can feel the air moving, which is transmitting the "sound waves", which can only work in a medium (stuff - air, water, steel, sand, whatever), but this is always happening - that's what happens in your ear - the air moves in & out on your eardrum, making it move, etc. giving you hearing (unless you're deaf, but I assume this is not the case.).
Sunny, I agree with you, except I think that speakers can work pretty well in the lower regions of sound as well. Think cinemas - their subs can go to ~3Hz. (that's 3 movements in/out per second). You feel that, rather than hear it. The only thing is the subs are very expensive. They cost upwards of $600 for one (MACKIE SW1500's are awesome for PA applications - I had 4 in one show - & one is able to peel gyprock off the wall
), but they can do it. The speakers are normally hidden behind the screen itself (which is why there isn't an ugly big box in the room), but the screen is "accoustically transparent", so sound can go straight through without rippling the movie picture.
This is not exactly a cheap/simple option, but I built a decent pair of speakers (think ~$1000 pair of bookshelf speakers, built for $220), & got a reasonably decent amp (old, & cheap, but still works OK). Plug that into a computer couple of adaptors, add my 12 inch car sub into the circuit, & for around $350-$400, cheaper, & HEAPS better than the "all in one" solutions. Admittedly, it's only 2.1, but hey, i'm woking on that.
. I used it for a CD recording at school one day, & that worked pretty well.
Hope that explains the question/gives you (proably more than you need to know)adequate detail/gives you a thought for future expansion.
Also, use Winamp (5.x - just the freebie one is OK) & AAC (Advanced Audio Codec) for audio on computer. Think MP3 convenience (Track listings/names/playlist, etc), with near or equal CD quality, & 5.1/7.1 channel playback easy, & Comparable filesize. (It's the codec used to compress the audio In DVD's, & the one (slightly customised) used by apple in their iTunes/iPod combination. I'm no iPod fan, but they at least got that right). So good.
Damn, why isn't there a "sound" subject for the HSC. Heck, Pro Stage/sound/lighting/video would be an awesome course. Why am I going for BEng (Computer) next year ?????
Ppeaking of video, Gotta love dual 3500 ANSI Lumen projectors on 4x3 Metre screens. Anyhow, this post is long enough as it is. I'll leave it there.