This article is from the rec.audio.* FAQ, by with numerous contributions by Bob Neidorff others.
Some people can build better than you can buy. These people are
either experts, golden ears, extremely well equipped, inspired,
or a combination of the above.
Some companies have plans available to entice you into buying
their drivers: Audio Concepts, Audax, Dynaudio, Focal, KEF, and
Scanspeak. Your success rate with these plans will probably be
very good IF your cabinetry skills are very good and IF you
follow the plans precisely. If you deviate (as everyone does),
anything is possible.
Stereophile has published three different plans designed by Dick
Olsher which are similar two-way ported systems. A recent one of
these was in Stereophile Nov '90, pages 94-127. Audio Magazine
published a plan called "The Pitts" by Ken Kantor, in Audio, Nov
'88 pages 65-71 continued in Dec '88 pages 73-77. This plan is
a two-way sealed box.
I have built one published design and one manufacturer's design.
I believe that both met my expectations. They took me a long
time to build, taught me a lot, were fun projects, and sounded
good when finished.
I also believe that a commercial system which cost what my parts
cost will never sound anywhere near as good as the one I build.
If you consider $2/hour for my time, however, building is
financial suicide.
Designing your own system is even more a can-of-worms, and
should be left to those with either a strong stomach, a very
forgiving ear, infinite resources, or excellent guidance.
 
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