Miscellaneous
This Purple (high frequency) Noise is by request with a frequency response between Blue and Violet Noise. It contains more highs than Blue, but less than Violet. Purple Noise is considered synonymous with Violet. I named it such because it seems a better title than Blue/Violet Noise (breaking the convention of the official noise color terminology). The noise energy is focused in the higher human listening frequency range with dynamic intensity (volume) dropping off at roughly 8dB per octave. A comparison of Blue and Violet was used to make Purple right in the middle according to my ears. There is little noise present below 2000hz. High frequency noise is used by listeners for many purposes I never dreamed of when originally posting years ago. In audio production, a tiny bit (-80 to -90dB) is often inserted into audio mixdowns to smooth out the perceived responses to the listener. This is called dither or dithering. Purple Noise is also good for testing high frequency response of speakers, to ensure tweeters and horns are functioning. Some listeners claim it smooths out the ringing in their ears. While I am an audio engineer by profession and not a music therapist, I find this fascinating. If you find a use for the purple noise, let us know in the comments. As always, thanks for listening. Dale