Sounds are ultrasonic at frequencies 20,000 Hz and up. Sounds are infrasonic at 20 Hz and down. Smartphone microphones can often pick up the lowest ultrasound and highest infrasounds. Practically speaking most people have trouble hearing sounds above 10,000 Hz, so they are missing lots of interesting sounds. These are sounds from birds, insects and even pet mice.

BlueWhale shifts very high pitched sounds down where human hearing is best, so you can have fun listening to sounds you might not ordinarily hear. Swarms of insects make high pitched sounds; so does rubbing one's hand on a shirt sleeve. Elephants and whales produce very low pitched sounds known as infrasound. (Although this software isn’t going to help you out with whales unless you have a hydrophone.) Many surprises await in ordinary things around the house. For example, brushing ones hand along some cloth is much louder in ultrasound than at regular hearing frequencies.

Use BlueWhale by first making an audio recording. Then play back the recording with the near-ultrasonic or near-infrasonic sound converted to normal hearing range.

Be sure to make short recordings. Once BlueWhale begins processing the signal for playback, it will continue until it is finished.

I appreciate receiving feedback or any recommendations for improvements to this application. Please contact me at [email protected] with any questions or recommendations that you may have.

For information about this or other AndWaves products, see www.andwaves.com