weighting speakers and resistance loading????

I have heard these terms while I was looking at reviews for my speakers, and am unsure as to why/how it would be accomplished. I have Mission M73 floor standing speakers

I have heard that weighting down the speakers helps the sound... How is this possible? My speakers have the speakers on the top of the cabinet that is ported out the back. Below that in a seperate chamber is a n opening that has a plastic cover on. At first I thought this was for the upgraded model and an extra port, but now I am thinking it is for adding weight. Do I just pour sand in there? how much do I add, and how does this help?

Also resistance loading, I think I know what this means, but how is it done, and what does it improve?

Thanks for any help.
Don't ever put send into the port. Speakers usually have a designated loading hole separated with the plane bellow the port. If such doesn't exist than don't bother.

A resistance loading needed when speaker represents a tough load. Usually you connect to the speaker wires a resistor in-series to match the amp's minimal load resistance.
The effect is you'll tame bass freequencies where your amp hasn't enough power to deliver.

If your amp clips at high freequencies than you need to decrease the resistance and you add in-parallel load resistor to the speaker binding posts so your speaker will have lower impedance. There you should make sure that your amplifier is able to deliver enough current to already decreased load otherwise you might face a blown woofer which is substantially more costly than tweeter.
If you imagine the speaker rocking back and forth a bit in reaction to the woofer's movements, you can see that it approximates an upside-down pendulum. The most effective place to add mass would be on top of the speaker.

I have had best results with a solid mass rather than with say sand or lead shot. But a solid 25-pound lump of lead is hard to come by. On the other hand, it's pretty easy to get a 25-pound bag of lead shot at a local sporting goods store that sells reloading supplies.

Put the 25-pound bag of lead shot in a heavy-duty zip-loc bag, and give it a turn or two of duct tape so that it makes as neat a sausage-shaped bundle as possible. Then put the zip-locked shot bag into a thick black sock. Tie a knot in the end of the sock. Then put the socked, zip-locked shot back into another thick black sock, knotted end first. Tie a knot in the second sock as well. This will give you an environmentally friendly, visually acceptable 25 pound weight you can position on top of the speaker cabinet (tuck the "tail" of the sock up under it for best looks).

This will help deaden panel resonances a bit, and the added mass will lower the natural rocking frequency of the upside-down pendulum to, hopefully, below the audible frequency range and improve the imaging a bit.

I have no useful experience with resistive loading.

Best of luck to you!

I was not going to put sand into the port. There is a seperate chamber below the speaker chamber that has the port sized hole in it. However this hole just has a plastic cap over it, and it is in no way connected to the speakers chamber, it is just an empty space on the bottom half of the tower.