GoldWave Inc.

Hi All
Hope some one can help me with how to Add white noise to a .wav file? I can make the white noise using the TOOLS Expansion Evaluator and adjust it's amplitude, but can't fiure out the adding !
Thanks

You can create a separate white noise file, and then use the Mix function to combine them.

Basically, you mix two files by selecting one whole file, clicking copy to copy it into the clipboard. Then, go to the other file and Mix it into the 2nd file. You can adjust the level of the mixed-in file during the mixing process.

And, watch your levels. When you mix, you can increase the level beyond 0dB and this can cause clipping when you save the file. You can also use the Maximize function to bring the level back down to 0dB after mixing.


And, just FYI - You used the word "add"... When digital signals are mixed, the individual samples are actually added (summed) together!

There is an "Add hiss to wave" preset under the Noise branch in the Expression Evaluator tool. The y value controls the amplitude of the hiss.

Chris

Thanks for the reply's. The rest of the story is iam trying to work backwards.....(to xmas!) in an effort to find out how the noise file might have been created as part of an experiment (they didn't take notes! ) i believe noise was added to the original file somehow!!. i havent been able to duplicate it with goldwave. I've put the before and after files at http://fcms.its.utas.edu.au/scieng/psyc ... _noise.zip
if you have any further comments or explinations of how the waveform might have been created that would be great.
Cheers