These are Nathan 5 Chime K5LA horns off of an Amtrak Locomotive. These are just sitting up here to show size. I can blow them with an air compressor. But to get full volume you need a lot of air. Not just pressure but volume. The inlet is 1/2 and optimum pressure is 130-140 PSI. You won’t get the volume of air to get the full effect with a cheap compressor and a small tank.
These are total overkill on a truck if you just want a loud horn. These are basically the largest real train horns you will find minus some physically larger Leslie SuperTyfon trains horns from older locomotives.
The trains I run have K5LA horns so I listen to these every day. The last thing I want is to hear them once I leave work! But they are LOUD.
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