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This page allows you to create repeating beeps. You can control the frequency and phase of the beeping. At its simplest, it works as a metronome. At a more advanced level, it repeatedly plays a riff. The effect is enhanced if you use headphones to separate the stereo channels.


Duration (sec): quantum (msec):
Left: frequency (hz): phase (degrees): left riff:
Right: frequency (hz): phase (degrees): right riff:

Input meanings

At the end of each field's explanation a range of sensible values is given. [x, y] denotes "from x to y".

Duration: the time of the run in seconds. [10, 10000].

Quantum: the minimum time period supported by your browser in milliseconds. [1, 100].

Separate left side and right side control over::

Frequency: the frequency of the color riff. [0.01,20]

Phase: the amount that the left and right sides are out of step. 180 degrees represents opposite. [0,180]

Riff: the frequency defines the length (period) of the riff. The period is divided into 32 equal segments. The string provided contains 32 0 or 1s. If the value is a 1, the beep sounds. [0 repeated 32 times, 1 repeated 32 times]

Example Suppose the frequency is 0.125, giving a period of 8 seconds. The riff divides this into 32 segments separated by 0.25 second. Suppose the riff is: [10001000100010000000000010000000] The beep will sound at 0, 1, 2, 3 and 6 seconds.

Note The beep lasts 10msec. This limits the frequency which it can play.


On pressing the PRESS TO START button:
Repeating sounds are produced. These should match the input specification. However, for high frequencies, more than 10 hz, say, the refresh rate will be too slow to keep pace. The maximum frequency depends mainly on the browser.