Amplification

Acme Sound Bass Speaker Cabinets - Andy Lewis' flat-response extended-range "Low B" line of 3-way bass speakers. Direct sales.
www.acmebass.com/

Bass Gear Review Page - Huge archive of bass-related user reviews including preamps, power amps, amp heads, speaker cabinets, combo amps, and effects.
www.bgra.net

Compact Bass Guitar Speaker Bottom - Len Moskowitz' famous compact bass cab plans. Gonzo sound for the do-it-yourselfer.
www.core-sound.com/bottom-article.html

Dana Music - Site from luthier Dana Sutcliffe offers a guide to match Ampeg amps and speakers correctly, as well as downloadable Ampeg manuals.
danamusic.com

ESP Projects - Audio projects including amps and preamps suitable for musical instruments amps, effects, and some neat subwoofer/processor plans for bassists.
www.sound.au.com/projects.htm

Fuchs Audio Technology - Design and hand-build tube amplifiers; includes model speficications and dealer network. Also offer a custom-build service.
www.fuchsaudiotechnology.com/

Harmony Central Amp Database - Large database of guitar and bass amplifier and speaker user reviews.
www.harmony-central.com/Guitar/Data/

valveamps.com - Collector and restorer of old valve guitar amplifiers describes his collection.
www.valveamps.com