ZeroGain
- Offers several discussion forums, articles, news and photos. Includes registration details.
- http://www.zerogain.com/

The Classic Speaker
- Support for acoustic research, repair and upgrade information, discussion forum, and links.
- http://www.classicspeakerpages.net/

Kenwood L-07D Direct Drive Turntable
- Unofficial site that focuses on this quartz PLL direct drive turntable developed in the 1970's. Learn more about technical specifications, history, photo gallery, parts and supplies.
- http://www.l-07d.com/

The Quad ESL
- Reference source on this classic electrostatic loudspeaker.
- http://www.quadesl.org/

Audiotools.com
- Collects information on past and present models of Hi-Fi and recording equipment along with links to, history and contact information for companies and individuals active in the field.
- http://audiotools.com/

Naks.com
- A thorough unofficial resource for Nakamichi tape decks.
- http://naks.com/

The Analog Dept.
- System gallery, online user manuals and maintenance information on Thorens turntables.
- http://www.theanalogdept.com/

Roger Russell and McIntosh
- Roger was former Director of Acoustic Research for McIntosh Labs. Offers information and photos of McIntosh equipment.
- http://www.roger-russell.com/

BlueFi
- Includes news and reviews. Plus a forum, polls and user feedback.
- http://www.bluefi.co.uk/