Accusonics, Inc. (USA)
Accusonics manufactures dependable ultrasonic horns and ultrasonic tooling for all makes of Ultrasonic Welders. We also sell used ultrasonic welders.
http://www.accusonics.com/

Beam
Truck air horns, stainless steel truck horns for trucks, trains, motorhomes and emergency vehicles. Truck horns at very competitive prices, order online - free shipping.
http://www.buytruckstuff.com/truckairhorns.htm

DDS Horns
Manufacturer of fiberglass horns and waveguides. USA.
http://www.ddshorns.com

Airchime Manufacturing Ltd. Air Horns & Whistles for Locomotives
Manufacturer of locomotive air horns and steam whistles for railway applications such as trains and locomotives including freight trains, passenger trains and rapid transit.
http://www.airchime.com/rail.asp

Industrial Ultrasonics, Inc
USA. Design and manufacture of a wide range of ultrasonic welding horns and fixtures. Also, refurbished welders, rebuilt converters, boosters, and ultrasonic welding accessories, and repair of existing ultrasonic horns. Detailed product catalogs.
http://www.industrialultrasonics.com/

Rainerialpex
Manufactures horns for car, trucks, boats. From Italy.
http://www.rainerialpex.it/

ALE Acoustic
Manufacturer of drivers, horns, woofer, crossover and diaphragm. Japan.
http://www.tachyon.co.jp/~sichoya2/ale/

Acapella Audio Arts
Acapella Audio Arts ist als Lautsprecherhersteller weit über Deutschlands Grenzen hinaus bekannt. Die hochwertigen Lautsprechersysteme mit Kugelwellenhörnern sind sowohl akustisch als auch optisch ein Genuß. Sie erinnern mehr an Skulpturen als an Lautsprecher.
http://www.acapella.de

Ongaro Marine Ltd.
Specializing in custom water craft air horns, ladders, and wiper blades.
http://www.ongaromarine.com/

Hilaunch
Sailplane accessories from Don Richmond. Includes adjustable tow hooks, control horns, and wing rods.
http://www.hilaunch.com