Is the roar of a finely tuned engine or that very particular exhaust note the only aural signature of your customized vehicle?

If so, consider this statement from Drew Hoffman, an automotive aftermarket parts producer: "A horn is your audio statement to the world."

Also consider a friend who recently bought a used Mazda Miata. He didn't find the tone of its standard horn as satisfactory as the car's driving dynamics, so he went to the aftermarket. Now, his car sounds just like a Ferrari -- at least from the sound of the car's horn.

Various companies produce aftermarket automotive horns. Among them is the Hoffman Group International LLC of Portland, Ore. Hoffman was a college student when he created a "shaved door handle" kit that replaced his car's factory-installed door handles with an electronic system that released the latch to open the door.

Since then, Hoffman's company has grown, creating and selling aftermarket products under a variety of brand names, including: AutoLoc (safety, lighting and interior, and vehicle body accessories); Keep It Clean (electrical parts and wiring); Kirgo (cooling fans, hoses); Protocol (door hinge systems); Stellar (security systems); Aurora (gauges); Vintage Products (wheels and differential covers); and Helix (suspension kits and components).

Among the AutoLoc products are 22 different styles of aftermarket automotive horns, which are grouped into vintage, novelty and train categories. Some horns are purely electrical. Others operate on compressed air systems. Hoffman said all the company's automotive horns are designed for installation by the do-it-yourselfer. Horns also can be stacked so one vehicle can be equipped with multiple sounds, he said.

Novelty horns include those that play "La Cucaracha" or "Dixie." Vintage horns include a wolf whistle, an air raid siren and a bull horn. Train horns sound like, well, big train horns and have names such as Midnight Express and Silver Bullet.

You can hear how each horn sounds on www.thehoffmangroup.com/autoloc.

Prices range from $20 to as much as $900.

For information, visit the Web site or call (800) 651-1970.