The Low Down

The higher the PSI, the louder your horn will be; 200 PSI being the max.  PSI Stands for Pound Per Square Inch).

The bigger the air tank, the longer your horn will sound; often times, also  longer it will take to fill the air tank again to re-sound.

The lower the AMP draw, the better the compressor; max should be 30

Pay attention to the gauge of your air line.  It DOES effect the volume and quality as well.

You want typically at least a 3 Gallon talk to run multiple horns.

A manual air valve, vs electric, will help you adjust the sound

How A Train Horn Works

Train horns operate by compressed air, flowing through a horn, and producing oscillation (via a diaphram assembly enclosed with a power chamber).  When air is applied to the horn, the diaphragm vibrates against a nozzel and produces sound.

The configuration and dimensions of the trumpet assembly, or “bell” determine the  frequency produced (measured in Hertz).