<div dir="ltr">Few people realize that the venerable Minimoog includes red noise.  But it's a modulation source not audio.  The front panel NOISE switch alternates between white and pink noise as an audio source, and also between pink and red noise as a modulation source.  Red noise as a modulation source sounds like smoothed S&H.<div><br></div><div>MC</div></div><br><div class="gmail_quote gmail_quote_container"><div dir="ltr" class="gmail_attr">On Tue, Mar 3, 2026 at 6:14 PM Thomas Hudson via Synth-diy <<a href="mailto:synth-diy@synth-diy.org">synth-diy@synth-diy.org</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-style:solid;border-left-color:rgb(204,204,204);padding-left:1ex"><div style="line-break:after-white-space">BTW, while researching creating green noise I came across a website for a Mac and iOS app:<div><br></div><div><div style="display:block"><div style="display:inline-block" role="link"><a style="border-radius:10px;font-family:-apple-system,Helvetica,Arial,sans-serif;display:block;width:300px;overflow:hidden;text-decoration:none" rel="nofollow" href="https://simplynoise.com/" dir="ltr" role="button" width="300" target="_blank"><table style="table-layout:fixed;border-collapse:collapse;width:300px;background-color:rgb(13,43,150);font-family:-apple-system,Helvetica,Arial,sans-serif" cellpadding="0" cellspacing="0" border="0" width="300"><tbody><tr><td><table bgcolor="#0D2B96" cellpadding="0" cellspacing="0" width="300" style="table-layout:fixed;font-family:-apple-system,Helvetica,Arial,sans-serif;background-color:rgb(13,43,150)"><tbody><tr><td style="padding:8px 0px"><div style="max-width:100%;margin:0px 16px;overflow:hidden"><div style="font-weight:500;font-size:12px;overflow:hidden;text-overflow:ellipsis;text-align:left"><a rel="nofollow" href="https://simplynoise.com/" style="text-decoration:none" target="_blank"><font color="#FFFFFF" style="color:rgb(255,255,255)">The original free color noise generator on the Internet. Hear what your mind has been missing…</font></a></div><div style="font-weight:400;font-size:11px;overflow:hidden;text-overflow:ellipsis;text-align:left"><a rel="nofollow" href="https://simplynoise.com/" style="text-decoration:none" target="_blank"><font color="#FFFFFF" style="color:rgba(255,255,255,0.698)">simplynoise.com</font></a></div></div></td><td style="padding:6px 12px 6px 0px" width="30"><a rel="nofollow" href="https://simplynoise.com/" target="_blank"><img style="display: inline-block; width: 30px; height: 30px; border-radius: 3px;" width="30" height="30" alt="cropped-web_sn_appicon_512-1-180x180.png" src="cid:ii_19cb70f593fbd2bc8d21"></a></td></tr></tbody></table></td></tr></tbody></table></a></div></div><br id="m_3538729242626118336lineBreakAtBeginningOfMessage"><div><br></div><div>In addition to noise colors, t also has beach sounds, fireplaces, babbling brooks, etc.</div><div><br></div><div>Fun little app.</div><div><br></div><div><br><blockquote type="cite"><div>On Mar 3, 2026, at 5:56 PM, Thomas Hudson via Synth-diy <<a href="mailto:synth-diy@synth-diy.org" target="_blank">synth-diy@synth-diy.org</a>> wrote:</div><br><div><div>Interesting idea and article. <br><br><blockquote type="cite">On Mar 3, 2026, at 4:58 PM, Mike Beauchamp <<a href="mailto:list@mikebeauchamp.com" target="_blank">list@mikebeauchamp.com</a>> wrote:<br><br>Hi Thomas,<br>Maybe take all of the different noises, and feed them into an interpolating scanner circuit (like this one: <a href="https://till.com/articles/scanner/" target="_blank">https://till.com/articles/scanner/</a> ) and from there you could control the output noise colour (and anything inbetween) with the wandering CV.<br><br>I wonder if the different noise colours all need to be derived from a single source for the crossfading to work.<br><br>Mike<br><br><br>On 2026-03-02 18:20, Thomas Hudson via Synth-diy wrote:<br><blockquote type="cite">I have an analog module that can generate blue, white, pink, and red (brownian) noise. I’m interested in how I might create a random walk using perhaps a sample/hold and smoothing function to produce a sort of wandering control voltage from each of these noise sources.<br>I also was recently introduced to green noise. From Wikipedia:<br> * The mid-frequency component of white noise, used in halftone<br>   <<a href="https://en.wikipedia.org/wiki/Halftone" target="_blank">https://en.wikipedia.org/wiki/Halftone</a>>dithering<br>   <<a href="https://en.wikipedia.org/wiki/Dithering" target="_blank">https://en.wikipedia.org/wiki/Dithering</a>>^[19]<br>   <<a href="https://en.wikipedia.org/wiki/Blue_noise#cite_note-19" target="_blank">https://en.wikipedia.org/wiki/Blue_noise#cite_note-19</a>><br> * Bounded Brownian noise<br> * Vocal spectrum noise used for testing audio circuits^[20]<br>   <<a href="https://en.wikipedia.org/wiki/Blue_noise#cite_note-comp.dsp_FAQ-20" target="_blank">https://en.wikipedia.org/wiki/Blue_noise#cite_note-comp.dsp_FAQ-20</a>><br> * Joseph S. Wisniewski writes that "green noise" is marketed by<br>   producers of ambient sound effects recordings as "the background<br>   noise of the world". It simulates the spectra of natural settings,<br>   without human-made noise. It is similar to pink noise, but has more<br>   energy in the area of 500 Hz.<br>Wondering how I might generate this other than using something like a bandpass filter tuned to 500 Hz using pink noise. I want to generate it in the analog realm.<br>TIA,<br>Thomas<br>________________________________________________________<br>This is the Synth-diy mailing list<br>Submit email to: <a href="mailto:Synth-diy@synth-diy.org" target="_blank">Synth-diy@synth-diy.org</a><br>View archive at: <a href="https://synth-diy.org/pipermail/synth-diy/" target="_blank">https://synth-diy.org/pipermail/synth-diy/</a><br>Check your settings at: <a href="https://synth-diy.org/mailman/listinfo/synth-diy" target="_blank">https://synth-diy.org/mailman/listinfo/synth-diy</a><br>Selling or trading? Use <a href="mailto:marketplace@synth-diy.org" target="_blank">marketplace@synth-diy.org</a><br></blockquote>________________________________________________________<br>This is the Synth-diy mailing list<br>Submit email to: <a href="mailto:Synth-diy@synth-diy.org" target="_blank">Synth-diy@synth-diy.org</a><br>View archive at: <a href="https://synth-diy.org/pipermail/synth-diy/" target="_blank">https://synth-diy.org/pipermail/synth-diy/</a><br>Check your settings at: <a href="https://synth-diy.org/mailman/listinfo/synth-diy" target="_blank">https://synth-diy.org/mailman/listinfo/synth-diy</a><br>Selling or trading? Use <a href="mailto:marketplace@synth-diy.org" target="_blank">marketplace@synth-diy.org</a><br></blockquote><br><br>________________________________________________________<br>This is the Synth-diy mailing list<br>Submit email to: <a href="mailto:Synth-diy@synth-diy.org" target="_blank">Synth-diy@synth-diy.org</a><br>View archive at: <a href="https://synth-diy.org/pipermail/synth-diy/" target="_blank">https://synth-diy.org/pipermail/synth-diy/</a><br>Check your settings at: <a href="https://synth-diy.org/mailman/listinfo/synth-diy" target="_blank">https://synth-diy.org/mailman/listinfo/synth-diy</a><br>Selling or trading? Use <a href="mailto:marketplace@synth-diy.org" target="_blank">marketplace@synth-diy.org</a><br></div></div></blockquote></div><br></div></div>________________________________________________________<br>
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