Cents

A cent is the logarithmic unit of measure used for musical intervals. One octave is 1200 cents. Each 100 cents is equal to a change in what is known as a semitone (for ex. the change from C to C# or E to F). The cents value of a tone is found by: 1200*log₂ (a/b), where a and b are the frequency of two known notes.

The range of the human ear is between 20 and 20,000 hertz (or between pitch values of 15.4868206 and 135.076232). But one of the more interesting points about cents occurs not between large cents intervals. It is instead smaller intervals such as how anything below 5 cents is imperceptible to humans. Not convinced? Test your hearing below.

Cents Tests

The following sound files are demonstrating the effects in changes of cents of a tone.

In each file the initial tone is that of middle C (frequency 261.6255653 hz). Following this is the tone with the altered new frequency. Then finally both tones are played simultaneously. For instance in One Cent Test middle C is played first. Following, the next tone is that of middle C but now it is one cent sharp (i.e. 262.655653hz.). Then both tones are played to together.

The four files, Twenty-Five Cents Test, Fifty Cents Test, Seventy-Five Cents Test, and Hundred Cents Test, correspond to microtonal quarter intervals. They break up the western standard semi-tonal interval, which is equal to one hundred cents, into four equal intervals. For some musicians it is necessary to be able to hear and recognize these differences.

Cents Test plays all of previous tones in one sequence.

Sound Files:

• One Cent Test
• Two Cents Test
• Three Cents Test
• Four Cents Test
• Five Cents Test
• Six Cents Test
• Seven Cents Test
• Eight Cents Test
• Nine Cents Test
• Ten Cents Test
• Twenty-Five Cents Test
• Fifty Cents Test
• Seventy-Five Cents Test
• Hundred Cents Test
• Cents Test