Electronics
- 545
- Taiwan Carol Electronics Co. Ltd.
- Taiwan. Manufactures a range of dynamic and multimedia microphones, such as wireless, supercardiode, reciting, CB, cable, mega phone, as well as speakers and power amps.
- 551
- Warren Gregoire and Associates
- Manufacturer of amateur radio headsets, desk microphones and push to and push to talks and also PC headsets for personal computers. Canada.
- 553
- Zero Impedance
- Add-on devices such as toroidal autoformer that have the ability to multiply a speakers impedance by 2x, 3x, or 4x.
- 554
- ATI - Amplifier Technologies Inc.
- Manufacturers of preamp/processor, stereo, multi channel and distribution amplifiers utilizing differential drive amplifier technology.