Like I said, I am fairly isolated from hearing a lot of builds
and I don't know how this would apply to theory, but....

If you have the 8 inchers you could make a quick transmission
line with some 6 in PVC., one elbow and a base. I have never
seen any PVC 6" pipe used... only 4".

Try some of these experiments and you place will look
like the set of McHales Navy or Oh Susanna! starring Gale Storm
and Charles Farrel. But you are prob'ly not that old. :-)

Here's the other PVC reference I have with some different
techniques:

Also here, for the more whimsical or projects to make
for kids:

http://www.t-linespeakers.org/projects/sampson/index.html

• Laying Pipe with Audio Leggo