High frequencies often become more difficult to hear with age.

But if higher frequencies are present, they need to be closer.

Younger people have the ability to hear lower and higher frequencies.

All services are run on route 1, due to its high frequency.

For high frequencies, however, its value is thought to be more sophisticated.

Want to bet I can't find a way to reach the high frequencies?

But it, too, begins to fall off at higher frequencies.

There the effects are brought about by the high frequency impressed.

These are usually bigger than the P waves, and have higher frequency.

This high frequency is thought to be due to the founder effect.