Sound Effect Generator

What it's for

Make short sound effects, about two thirds of a second long, each built from a number called a seed. The same seed always gives the same sound, so a sound you like can be made again from its number alone. It’s a browser version of SEG, a command line tool for the Mac, and a seed gives the sound SEG makes.

For example, when your automations all end with the same system beep, play random sounds until you have one for each, note their seeds, and save each as a WAV file for the automation to play.

How to use it

Random sound picks a seed, puts it in the Seed box and plays it; press it again for another. Play this seed plays the number in the box, and Save saves the sound as WAV, MP3 or AAC, named seg-<seed> with the format’s extension. The message names the seed and what it made, such as “Pulse tone at 728 Hz with 2 harmonics, noise, echo, distortion.”

Seeds are whole numbers from −2,147,483,648 to 2,147,483,647; bigger ones wrap round, as in SEG, and −1 means a random one. Change the sound keeps the seed’s character and changes one part, like SEG’s -c settings file: Pitch sets the base pitch, Reverb room the size of the reverb, Echo the longest echo time (the seed picks a time between half that and it), and Drive the distortion. Reverb, echo and distortion only change a seed that has them. Volume scales both playing and saving; at 100% the file is as loud as SEG makes it. Copy a link keeps the seed and settings.

Example

Enter this seed and press Play this seed:

12345

The message reads “Seed 12345: Pulse tone at 728 Hz with 2 harmonics, noise, echo, distortion.” Running seg 12345 in SEG plays the same sound.

Good to know

Every sound is mono, 44.1 kHz and 0.7 seconds, the last part of it silent, as in SEG 1.0.0. The samples are worked out in a different way from SEG’s, so a saved file differs from SEG’s by tiny amounts you can’t hear, and a later version of SEG may make different sounds from the same seed. MP3 and AAC lose a little detail, as compressed formats do; WAV keeps every sample.