Sure there is Terry, at one time you could send your Cibola or Vaquero back to Tesoro, and if it was under warranty, they would modify it for the high tone for $15 bucks, $50 out of warranty.
tag1260, there's several you tube videos of what a high tone Cibola and Vaquero sound like. As to how to tell, I assume you just have to turn one on. I assume the hobbyists can easily modify one, I didn't search for the instructions.