Here's a good video of some different K5LLA combos. The Nathan Airchime K5LLA is commonly found on EMD SD70ACe locomotives and typically speaking is a very common horn on today's railroads alongside the K5HL variant. The sound of an K5LLA is achieved with a 2-Piece 1L bell and was before the switch to Raised Letter castings with a 1-Piece 1L. Many describe the older K5LLAs as having a very musical sound. Also thrown in is an old Leslie S3L probably manufactured around the 1970s or early 80s. Many people have K5LLA videos up on YouTube but I felt there was a need for more explanation and description of combinations for railfans to hear and see.