An idea that may or may not work....

[protokatie]

Ok, my boss is getting rid of his old work computer (P3, monitor, speakers with a bass box)

The bass box is one that has the speaker pointing directly at the floor, and is rather large for a computer bass box. My idea is, if I made a thin platform that starts inside the cab and extends outward in front in such that you are standing on it while playing, would one of these bass boxes make the platform vibrate enough that a player would really feel it? Or would this just be a bad idea and just end up distorting the sound too much?  (BTW the bassbox would be screwed to the platform on the inside of the cab)

[MaximRecoil]

Ideally, an enclosure for a low frequency driver does not vibrate at all. Some people go so far as to make the enclosure from poured concrete, but usually at least 3/4" MDF or Baltic Birch plywood is used (often with double thickness for the baffle) combined with internal bracing to minimize enclosure resonance. Vibrations from the enclosure "color" the sound, which is not a good thing.

So, it depends on how well the "bass box" was built. If it was built cheaply, it will probably vibrate a good deal. I wouldn't worry about distorting the sound. The only sound you would be changing by standing on a speaker box is the sound from the box resonance itself, which is undesirable in the first place. Standing on it would deaden the vibrations to a degree, which should/could be a good thing in terms of sound quality.

[protokatie]

So, to get the platform to vibrate well, would I be better off just bolting 12 inch speaker elements directly down on the platform? Or is there a better way to get floor/platform vibration?

[MaximRecoil]

So, to get the platform to vibrate well, would I be better off just bolting 12 inch speaker elements directly down on the platform? Or is there a better way to get floor/platform vibration?

I'm not sure exactly what you have in mind without seeing some sort of diagram. Are you wanting to put the box inside the cabinet but have it sitting on a board/platform that extends out in front of the cabinet?

In any event, you could attach a subwoofer(s) directly to the platform (make sure they are designed for "free-air" use) and given enough power (and make sure they can handle the power), they should vibrate the platform quite well. However, sound quality probably won't be great in such a setup. You won't be able to have both good SQ and a vibrating platform really, because for good SQ you try to minimize external vibrations, including enclosure vibrations; so if the goal is vibrations, you're going to have to sacrifice SQ.

[protokatie]

I'm not sure exactly what you have in mind without seeing some sort of diagram. Are you wanting to put the box inside the cabinet but have it sitting on a board/platform that extends out in front of the cabinet?

yes, that is the basic layout idea for it. As far as SQ goes, it would only be the lowest of BASS that the "vibrator platform speakers" would get, I would prolly have it on a seperate EQ than the speakers in the cab meant for audio...

[MaximRecoil]

I'm not sure exactly what you have in mind without seeing some sort of diagram. Are you wanting to put the box inside the cabinet but have it sitting on a board/platform that extends out in front of the cabinet?

yes, that is the basic layout idea for it. As far as SQ goes, it would only be the lowest of BASS that the "vibrator platform speakers" would get, I would prolly have it on a seperate EQ than the speakers in the cab meant for audio...

Yeah, but SQ applies to even low frequencies. There is good sounding bass and there is bad sounding bass. There is no harm in trying it though, aside from the fact that it will probably be pretty expensive. You can try the PC speaker setup, but for one, those usually aren't all that powerful, and two, it is already in an enclosure which, if built decently, won't vibrate much anyway (meaning not much vibration to transmit to a platform). If a (wooden?) platform is sturdy enough to stand on, it is going to take quite a bit to get it vibrating significantly.

[NickG]

If you need stronger vibration, there are products designed for this purpose.  They are referred to as bass transducers, butt-shakers, tactile transducers, and even butt-kickers.  They are designed to shake the wood or other materials that you mount them directly to instead of shaking the air like a common speaker.

[protokatie]

If you need stronger vibration, there are products designed for this purpose.  They are referred to as bass transducers, butt-shakers, tactile transducers, and even butt-kickers.  They are designed to shake the wood or other materials that you mount them directly to instead of shaking the air like a common speaker.

Ahh thanx, that would prolly work best.