An excellent sonosub primer with tons of construction pictures.

 WaterHeaterSonosub

Another good sonosub site.

 Passive Radiator Design

Information on passive radiator design from Lambda Audio.

Audio Innovation

Interesting projects using conventional subwoofers and speakers.

 DIY Subwoofers

Comprehensive listing of different subwoofer types and design information.

The SonoSub Link Page

Tons of links to sonosubs and conventional subs.

The Loud Speaker Driver Selection Guide

The definitive web guide to selecting speaker drivers and designs. This is the first site to browse for your first project.

This to That

How to fasten anything to anything.

Patman's Center Channel

Construction pictures and design info for center channels. Tons of construction pictures.

The Bass Zone

Several interesting projects and links to the DIY basslist which is a tremendous source of information.

Adire Audio

More drivers and passive radiators.

Stryke Audio 

Source of high quality subwoofer drivers.

Parts Express 

Best internet source for anything you need to build your own speaker The also have projects speakers as well as a tech talk page.

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