Contemporaneously, and apparently in response to this regulation, AirChime began producing 5-chime K horns for US locomotives that made use of the low-pitched 1L bell, which plays C (261Hz).

The K5HL is standard equipment on new GE locomotives, and the K5LLA is standard on new EMD's. Oddly, the K5HL is usually mounted backwards, with four of the bells facing the rear of the locomotive.

2020年9月15日 · 2003 - 2-piece sandcast 1L bell introduced into mainstream use, notably for the K5HL GEVO horn. 2006 - Late 40Ks or 50Ks serial change to raised letter models (Airchime on bell sides as well as number).

: Nathan N3 + Nathan K5LA 1f, 1g + Nathan K5HL 2004 #2! 4 new amazing horns for you to enjoy! NEWS (3/5/13) - Updated Website Organization, and KUID List page. New Horns! : Nathan K5L 2 + Nathan K3H VIA Rail 2. NEWS - New route by Trucks91- Midwest Lines Version I and updated version of Missouri Lines. NEWS - 17 New Horns Available

2015年9月22日 · The K5LLA was produced in the same fashion as the K5HL with different bells. The main tone difference is the change to using the raised-letter bells and the two-piece 1L on pre-2007 horns. The K5LLA did not change as dramatically as the K5HL did with the manufacturing changes.

2015年10月10日 · Think about how these two horns are mounted on a locomotive. K5HL’s are mounted backward with the #2 facing forward. K5LLA’s are mounted with the 1L reversed.

With the new tuning and lower bracket, the K5LA was born, the “L” standing for “Low Bracket” and the “A” to designate American tuning. By the 1980s, the K5LA was the most popular horn used around the world and remains so to this day.