Down firing sub tweeks

I have an old school setup.
Nikko Alpha 2 amp
Nikko Beta 2 preamp
Nikko Gamma 1 Tuner
ADC Sound Shaper
Cambridge Audio Azur 540 CD player
Nikko Np750 turntable
BIC beam box antanae
I run 2 pair of DCM Time Windows 1A
and 2 DCM 10 inch subs.
My set up is in a 12' x 20' room with not the greatest set up as far as accoustics. I will try the cones, but is there any opinion on using say a granite base or the auralex sub dudes?

The bases made by Zmanastronony are what I was thinking. What are they made of ? What did you notice as far as an improvement ?

I decided to try and experiment with sub bases. I made them out of (2) 3/4" thich MDF glued and screwed together. I then glued on 1/2" oak plywood for a 2" total thickness. I wrapped the out side edges with aspen wood all stained to match the componet stand I built previously. Not willing to spend big bucks on cones at this point I used 3" x 5/16" brass screws that extend 1" below the bottom for spikes. Once the 5 coats of gloss clearcoat set up I will try them out and report on any impressions.

Well I finished the sub bases, and after an evening of listening here are my thoughts:
-Well worth doing if you have carpet. Bass is clear, and
tight. The carpet seemed to muffle the sound some.
- My room is a finished room over the garage, and if you are looking to this idea to keep the sound in rooms below you quieter, it will do that also. But, you can still hear it below, but definatly not as loud.
- Thanks for the info. on the spikes from Parts express, I will order those as I believe this tweek is a success.
You can see them in my system photo.