Friends, I have a 2.218 ft. cu. sw enclosure that I made 14 years ago for an old Cerwin Vega XL-12S.

I want to reduce the the volume to 0.71 cu. ft. to use as a sealed enclosure for a RSS315HF-4 12. Temporarily.

What do you think about this Cra Kra idea to achieve my goal, I am thinking that I can use plastic containers?

The following jar pictured has a shape that should not compress with even pressure from a sw, especially if I fill it with foam insulation.

I do not want to increase the weight with 1.5 cu. ft. of wood blocks, the box, S/W and the plate amp each are heavy on their own.

Dam Skippy!
I plan on making a larger ported enclosure for the RSS315HF-4 12 and returning the Cerwin Vega to this box to give to someone so I don't want to do anything permanent to this enclosure.

 

I would suggest using a concrete tube former. These are also known as sonotubes. Alternatively a large diameter PVC pipe. Most importantly, to figure out the length of tube/pipe needed you would use the following formula: Pi (3.14) * (Tube Diameter*2) * (Tube Length) / 1728 = Cubic Ft Volume. So for example, you want a volume of 0.75 ft2, so if you use a 12" diameter sonotube or pipe.. [ 3.14(PI) * (12*2) * 17 /1728 = 0.74138 ft2 ] so a 12" diameter by 17" long tube would be just under the size you want and a 12" x 18" tube would be just a little bit over (0.785 ft2).
By simply looking at these calculations, you will see that the jar you are taking a picture of is NO WHERE near the correct size enclosure you would need. I hope this helps!

 

I might be able to use four six inch by X PVC tubes capped on both ends. I can get the tube free, the problem is that those caps cost eight dollars each, I don't want to spend $35 on a temporary thing.

I think that I am going to go with the insulation foam filled plastic bottles.

I am thinking about making an egg shaped sub enclosure that looks like "Alien Eggs"