This article is from the Car Audio FAQ, by Ian D. Bjorhovde (email@example.com) with numerous contributions by others.
Various enclosure design software is available via ftp from
The most popular program there is Perfect Box, which is in the file
`perf.uu' (or `perf.zip').
Note that NO program can tell you what enclosure is best for YOUR car!
The program does not take into consideration your space limitations,
the type of car you drive, the type and number of mid-bass drivers you
use, your musical preferences and the goals you have for your system.
Many people follow (blindly) what a computer program says is "optimal,"
and end up unhappy with the results. Therefore, it is always a good
idea to discuss a design you think looks good with a qualified
installer or (even better) with the manufacturer.
For an overview of many programs and devices available for enclosure
design, obtain the file `sahfsd01.doc' at the ftp.uu.net archive. The
filename stands for "Software and Hardware for Speaker Design", and was
added to the archive in June 1994 by an anonymous contributor.