From my building experience, the most bang for the
buck is PVC pipe. Parts are cheap. You don't have to have
a shop and they look like they're from the future.

Just about any full range driver will work-- RS 1197
or upscale FE127e's. There's prob'ly a 4 " from Tangband
that will work too.

You mount the speak on one end and the other end is open.
Allow about 80 inches in between. Supply elbows to shape
to taste.

Here's a shorter version:

• PVC periscopes

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

I've wondered where to get the good stuff as far as Sonotube goes.

The stuff at Home Depot in USA is pretty flimsy and looks like it
would need bracing just to stand up.

On the center of a circle thing, I was considering getting some
MDF pre-cut 'table tops' and at Home Depot but I haven't found
the right dimension-- either too big ot too small to begin with.

What kind of woodworking tools do you have? I've seen homemade jigs for bandsaws that are used to cut exact circles. Also, it might sound silly, but concrete is pretty easy to work with and the forms are easily built. With a little practice, one can get a glass smooth finish. My wife and I played with concrete for a while; we are trying to make our own kitchen counters tops. We got to where we could lay 3' x 3' sections with simple forms and basic tools to almost a mirror finish. Concrete can also be colored rather easily to give some rather intersting effects......Colin

My tool collection is pretty meager. A hacksaw works to
cut down PVC pipe. An electric hand drill and drill guide
can make straight pilot holes and a few hole saws mounted in
the drill chuck can do cutouts for up to 4" drivers. I also
own 4 clamps. :-)

The most versitile tool I got was a generic RotoZip
or 'spinsaw' ($30 on sale) which comes with an assortment of add-ons to cut larger circles (though sometimes not ver true), will
take 3/8 shank standard router bits to do various depth of
cut rabbets and chamfers for driver holes. I'd rather
have a good router though.

Add a few screw drivers and that's about it. Up til
recently I had an arrangement for a fellow whom I sold
a table saw to (an estate sale) to cut wood, but I have
lost communication w/him so I'm back to 1.) looking for a
new cutter or 2.) exploring the use of a sawboard (see
craftsmen section here.)

I am not a home owner. I'm 57 and live in a one bedroom
apt. So even if I could afford good tools I couldn't
use 'em.