Echolocation

Transmutation [sonic]
Level: Alchemist* 4, Bard * 4, Druid * 4, Hunter * 4, Sorcerer */Wizard * 5
Components: V
Casting Time: 1 Standard Action
Range: personal
Target: you
Duration: 10 minutes/level
Saving Throw: -
Spell Resistance: -
  You can perceive the world by creating high-pitched noises and listening to their echoes. This gives you Blindsight to a range of 40 feet. The echo-producing noises are too highpitched to be heard by most creatures, and can only be detected by dragons, other creatures with this ability (such as bats), and creatures with hearing-based Blindsense or Blindsight. You cannot use this ability if you are deaf, and cannot detect anything in an area of silence.