diyAudio.com  
   Web community dedicated to DIY audio projects and discussion.
   http://www.diyaudio.com/

Klaus Boening's Tube and Audio Homepage  
   Describes a 50 watt tube power amplifier for high end applications, including schematics and description of the circuitry.
   http://www.klaus-boening.de/

Pass Do-It-Yourself  
   Projects by Nelson Pass including amplifiers, preamps and loudspeakers. Site offers information on circuit boards, FAQs and how to articles.
   http://www.passdiy.com/

Elliott Sound Products - The Audio Pages  
   Information for audio DIY hobbyists. Articles, construction projects, links, sources.
   http://www.sound.au.com/

Promitheus DIY Audio site  
   Includes projects and articles about amplifiers, preamplifiers, speakers and cables.
   http://mitglied.lycos.de/Promitheus/

Pete Millett's DIY Audio Pages  
   Depository for a variety of audio designs and projects, especially tubular amplifiers. Site offers photo gallery and details on the author's projects, downloadable PDF documents, and technical diagrams.
   http://www.pmillett.addr.com/

CoolTune Audio Projects  
   Marco Rutz shares his experiences and projects in design, acoustics and recording. Personal observations, current and past projects, photo gallery, and high-end systems are showcased.
   http://home.tiscalinet.ch/cooltune/

RJM Audio Cable  
   A resource for the design and construction of speaker cables, interconnects, and digital cable from inexpensive and commonly available wire and cable products.
   http://www.geocities.com/rjm003.geo/rjmaudio/index.html

Leon's Audio Page  
   Showcases the author's build of tube amplifiers, pre-amplifiers and restorations of tube radios.
   http://leonaudio.snn.gr

Lighthouse Electric - Hobby Electronics  
   Projects and tutorials. Switched Mode Power Supplies, Vacuum tube and solid state audio amps.
   http://www.lh-electric.4t.com/

Wade's Audio And Tube Page  
   Discussion of vacuum tube audio amplifiers and high fidelity equipment with photos and schematic diagrams.
   http://www.angelfire.com/vt/audio/

Gary's Vacuum Tube Page  
   Vacuum tubes for antique radios and tube audio gear.
   http://www.the-planet.org/

AudioClub  
   The site for audiophiles and/or fanatics.
   http://audioclub.supereva.it/indexEn.html

Decibel Dungeon  
   Beginners Guide to all matters relating to DIY hi-fi. Everything clearly explained with text and pictures.
   http://www.decdun.fsnet.co.uk/

Chris VenHaus Homepage  
   DIY resource for Audiophiles. Includes recipes for Cat5 speaker cable, fine silver interconnects, and power cords.
   http://www.geocities.com/venhaus1/

Boozhound Laboratories  
   DIY site specializing in tube audio, vintage style guitar amps, mad science and all around DIY hooliganism.
   http://boozhoundlabs.com/

Tube Amplifiers by Giovanni Schiavon  
   Offers a range of drawings, photos of components and complete builds, downloadable manuals, and descriptions to build vacuum tube amplifiers.
   http://web.tiscali.it/ampli/

Pjay's DIY Speaker Building Page  
   Information on speaker building: how to build speakers, find drivers and a listing of projects.
   http://www.members.aol.com/pjay99site/speakerhome.htm

London Live DIY HiFi Circle  
   British-based informal group focused on advancing do-it-yourself audio reproduction features membership details, overview of current and past projects, a newsletter, articles on systems, and links.
   http://www.earthcurrents.com/london-live/

DIY Hifi, Audio and ELectronics  
   Includes datasheets and reference articles on audio and headphone amplifiers, preamplifiers, head and phono amps.
   http://blackwidowaudio.tripod.com/

Guitar Electronics Projects  
   Self-built guitar tub amplifiers. Showcases design and stories beyond tube amp building, effects pedal building, and related music projects.
   http://www.freewebs.com/amp_build/

PCB-Design  
   Kristijan Kljucaric offers his blue-colored PC board (PCB) designs for high-end DIY projects supported by Pass Labs, including amplifiers, pre-amps, crossovers, and power supplies.
   http://web.vip.hr/pcb-design.vip

nMine.com Developments: Multi-amplification DIY Project.  
   Description and photos of multi-amp PCB with three integrated amplifiers each PCB and 24 dB/Octave Linkwitz-Riley Electronic filters. Configurable as a bi-amp or tri-amp.
   http://www.nmine.com/multiamp.htm

XO - An Excel Crossover Design Tool  
   Passive 2-way crossover spreadsheet design tool. Models allow complex speaker impedance, acoustic target shapes, series or parallel designs, and impedance compensation circuits.
   http://www.geocities.com/mghjch02

Matthew Anker's Electrostatic Loudspeaker Page  
   Information on HiFi electrostatic loudspeakers. Contains information on how to get started and build a basic panel.
   http://www.sacdmods.com/ESL/index.htm