It takes surprisingly little to make your own functional speaker. Create and plug them into your iPod or standard audio jack to enjoy a classy sound.
8 years +
Frequencies above 20,000 Hz are too high to be heard by humans but some animals, such as dogs, can hear above the human range. Frequencies below 20 Hz are too low to be heard by humans but since children hear better than adults, they can hear more subtle sounds like the humming of fluorescent lights.