SWR Sound Corporation
- Manufacturer of professional amplifiers. Site includes product descriptions, retailer lists, support information, and catalog.
- http://www.swrsound.com/

Electrocompaniet
- Manufacturers of preamplifiers, integrated and power amplifiers. Product and contact details available.
- http://www.electrocompaniet.com/

Neva Audio
- Manufacturer of professional power amplifiers.
- http://www.nevaaudio.com/

Tripath Technology, Inc.
- Developers of digital amplifiers for the audio and communications markets.
- http://www.tripath.com

Chevin Research Ltd
- Supplies a range of high powered audio amplifiers, engineered and built for professional users.
- http://www.chevin-research.com/

Grommes Precision Electronics, Inc.
- American manufacturer of original, custom, and private labeled audio and electronic components for use in commercial, consumer, and industrial applications.
- http://www.grommesprecision.com

CR Developments Ltd.
- Manufacturer of tube transistor amplifiers.
- http://www.crdevelopments.com

QSC Audio Products
- Power amplifiers, digital signal processing and signal transport.
- http://www.qscaudio.com

Sunrise Engineering and Design Inc.
- Makers of the TRUE Precision 8 Microphone preamp. News and reviews, technical support, and product ordering information.
- http://www.true-systems.com/