Getting the right horn

[AntonioFP45]

Aloco is correct. 

A bit more info.  The Nathan K3 "Canadian tuned" versions are categorized as the K3H and K3L.  A number of Canadian units also used the Leslie S3K, which is the horn sound heard on BLI's RSD-15.  These horns are also on a number of U.S units as well.

Would be great if the manufacturers would make or already have the K3H and K5H sounds as, imho, they are sweet sounding horns. You can hear some prototype sound samples on this link: 

http://atsf.railfan.net/airhorns/k3l.html

 

[aloco]

The Canadian horns were made by Air Chime, and the CP SD40 fleet was equipped with the K3 series horns.  The Canadian K3 was tuned to an E flat minor chord.   American horns were tuned to a major chord, either A major or B flat major. 

[CPPedler]

 

   I want to upgrade two of my BLI SD40-2's with the QSI Upgrading chips, so that the horn sounds more like a C.P.Rail horn rather than the present offering on the decoder.

   However I'm not sure what horn C.P. Rail uses or if the Upgrade chip will do the business, as there seems to be a lot of horn tones available.

  Can anybody please advice me of the right horn.     Thanks in advance.    CPPedler