[Note: These tests are not intended to diagnose, treat, or cure any disease. I just thought they would be neat to make.]

Test One: Frequency Threshold

In the following test, seven bursts of noise are played, each (roughly) the same volume as the last. To test your ability to hear high frequencies, note the burst after which you can hear no more. Make sure you have your volume at a reasonable level before playing the test file, since you would not want to damage your hearing while trying to test it:

Frequency test

The first burst plays frequencies at 10,000 Hz and above. People middle-aged and younger without especially damaged or congenitally weak hearing can detect these frequencies.

The second burst plays frequencies at 12,000 Hz and above. Some middle-aged people are unable to hear frequencies around this level.

The third burst plays frequencies at 14,000 Hz and above. A number of middle-aged people cannot hear frequencies at or past this level.

The fourth burst plays frequencies at 16,000 Hz and above. Quite a few middle-aged people cannot hear these frequencies.

The fifth, sixth, and seventh bursts play, respectively, frequencies at 17,000 Hz, 18,000 Hz, and 19,000 Hz and above. Young children can often continue to hear frequencies at all these levels; the ability of older children and young (20-30) adults to hear them drops off as frequencies and ages increase.

"20-20," or 20 Hz to 20,000 Hz, is often said to be the "perfect" range of human hearing.

An important thing to note before you run to the doctor and scream, "Help, my hearing's gone!" is that many types of headphones and speakers will not play frequencies above 16,000, 14,000 or even 12,000 Hz in some cases. So if you could hear stuff all the way to the end in this test, you probably have some decent audio equipment in addition to sensitive ears.

Test Two: Pitch Differentiation

In the following test, ten pairs of notes are played. The first note in each pair is always at a pitch of 440 Hz, while the second note is slightly lower in pitch than the first one. With each successive pair, the difference between the two tones increases slightly -- that is, the pitch of the second note in a pair will be lower than the pitch of the second note in the previous pair. To test your ability to tell the difference between two pitches, note the first pair where you can clearly tell that two notes of a pair are different:

Differentiation test

A "cent" is a very small musical interval -- 1/1200th of an octave. The difference within the first pair of notes is 4 cents; to be able to detect a difference smaller than 5 cents is a pretty rare ability.

The difference within the second pair of notes is 8 cents, and 12 cents within the third pair; a good number of people can distinguish between two pitches this far apart.

The difference within the fourth pair of notes is 16 cents, and 20 cents within the fifth pair; very few people fail to detect a difference around this range.

If you found that you could not detect a difference within any pair of notes at all by the end of this test, you probably should not be tuning any instruments.