Audio Systems: boxes, polk speakers, rms power


Question
i am hoping this question is not way beneath you. I drive a fork lift for a living I am in this thing most of my awake life. I am limited for room--I am putting in a stereo strapped to the top cage. I have a stereo out of a 99 neon and I have made 2 speaker boxes for a pair of 4x6 polk speakers---Question is ---the boxes are 6x6x3---should I put something in the empty space in the boxes or not and if so what.?--hope you can help a bit --it"s pretty important to me as I live in this damn thing___THANKS

Answer

In short, I do not think it will be much help.
Of course, from the getgo, this system will be about tunes you can hear and so not much about accuracy.

However, I would suggest trying it, for sure. As to what will sound better (overall) only your ears and testing will tell you.
Generally, you should use some filler to enhance the bass damping factor but in this situation, with their small size (as in, not intended for low bass reproduction), I do not think it will help much (even to a trained ear in a quiet room). With the added ambient noise at work, I do not think it would be helpful at all.
Just keep in mind that those will NOT reproduce low bass (even at rated RMS power with a dedicated amp.. much less with the power you will get out of that Neon one), so do not even try to boost it or use loudness/bass to compensate. Since you do not have much available wattage, you will only damage them by trying to compensate for poor bass by using equalization, ect.
It is likely you would only peg the stereos' amp and then the mids/highs will distort [only cause you are trying to make them do impossible low bass]. You can damage the stereo and the speakers in this way.

On the lighter side:
I think this ForkLift tunage concept is a neat idea (I drove one for years are Carnation) and if it were me, I would attempt adding a small 8" subwoofer, if possible.  hehee!

Cheers