<?xml version="1.0" encoding="UTF-8"?>
<rss xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:content="http://purl.org/rss/1.0/modules/content/" xmlns:atom="http://www.w3.org/2005/Atom" version="2.0"><channel><title><![CDATA[adaptive sample rate and harmonic aliasing in PD?]]></title><description><![CDATA[<p>hi all .. i have a tricky problem and am kind of stuck.</p>
<p>i want to simulate a sampler with variable samplerate, more precisely the sequential circuits prophet VS. ... this synth used wave data with 128 samples each and had 32 oscillators that were tuned via subdividing a fixed clock rate into variable bitrate DACs.</p>
<p>ie. playing a sample at 200 hz clockrate resulted in a DAC samplerate of 200 x 128 = 25800 hz ... this of course results in totally different aliasing than fixed samplerate because the nyquist frequency moves harmonically with each tuning.</p>
<p>im trying to simulate that in PD with over/undersampling but how?</p>
<p>here is how it sounds now: <a href="http://tindeck.com/listen/jvchf" rel="nofollow">http://tindeck.com/listen/jvchf</a></p>
]]></description><link>http://forum.pdpatchrepo.info/topic/11176/adaptive-sample-rate-and-harmonic-aliasing-in-pd</link><generator>RSS for Node</generator><lastBuildDate>Tue, 06 Oct 2026 07:03:29 GMT</lastBuildDate><atom:link href="http://forum.pdpatchrepo.info/topic/11176.rss" rel="self" type="application/rss+xml"/><pubDate>Thu, 21 Dec 2017 16:38:55 GMT</pubDate><ttl>60</ttl><item><title><![CDATA[Reply to adaptive sample rate and harmonic aliasing in PD? on Fri, 22 Dec 2017 07:00:42 GMT]]></title><description><![CDATA[<p>hi all .. i have a tricky problem and am kind of stuck.</p>
<p>i want to simulate a sampler with variable samplerate, more precisely the sequential circuits prophet VS. ... this synth used wave data with 128 samples each and had 32 oscillators that were tuned via subdividing a fixed clock rate into variable bitrate DACs.</p>
<p>ie. playing a sample at 200 hz clockrate resulted in a DAC samplerate of 200 x 128 = 25800 hz ... this of course results in totally different aliasing than fixed samplerate because the nyquist frequency moves harmonically with each tuning.</p>
<p>im trying to simulate that in PD with over/undersampling but how?</p>
<p>here is how it sounds now: <a href="http://tindeck.com/listen/jvchf" rel="nofollow">http://tindeck.com/listen/jvchf</a></p>
]]></description><link>http://forum.pdpatchrepo.info/topic/11176/adaptive-sample-rate-and-harmonic-aliasing-in-pd</link><guid isPermaLink="true">http://forum.pdpatchrepo.info/topic/11176/adaptive-sample-rate-and-harmonic-aliasing-in-pd</guid><dc:creator><![CDATA[lilakmonoke]]></dc:creator><pubDate>Fri, 22 Dec 2017 07:00:42 GMT</pubDate></item><item><title><![CDATA[Reply to adaptive sample rate and harmonic aliasing in PD? on Thu, 21 Dec 2017 21:39:11 GMT]]></title><description><![CDATA[<p><a class="plugin-mentions-a" href="http://forum.pdpatchrepo.info/user/lilakmonoke">@lilakmonoke</a> these dphasor~ abstractions try to do something similar I think <a href="https://forum.pdpatchrepo.info/topic/6759/new-anti-aliasing-and-phase-distortion-abstractions" rel="nofollow">https://forum.pdpatchrepo.info/topic/6759/new-anti-aliasing-and-phase-distortion-abstractions</a>.<br />
Post number 4 describes it in more detail.</p>
]]></description><link>http://forum.pdpatchrepo.info/topic/11176/adaptive-sample-rate-and-harmonic-aliasing-in-pd/2</link><guid isPermaLink="true">http://forum.pdpatchrepo.info/topic/11176/adaptive-sample-rate-and-harmonic-aliasing-in-pd/2</guid><dc:creator><![CDATA[weightless]]></dc:creator><pubDate>Thu, 21 Dec 2017 21:39:11 GMT</pubDate></item><item><title><![CDATA[Reply to adaptive sample rate and harmonic aliasing in PD? on Fri, 19 Jan 2018 06:55:09 GMT]]></title><description><![CDATA[<p>this is really intersting and based on the same idea i think. im not sure if it will work with samples but maybe it includes a solution to that too. thanks!</p>
<p>if somebody has another solution please let me know. variable samplerate is the solution to all disharmonic aliasing! it will still alias but in a good way ... here is an interview with one of the inventors of this synth where he explains why ...</p>
<p><div class="embed-container"><iframe src="//www.youtube.com/embed/_U9RpS_2RSk?t=1641" width="640" height="360" frameborder="0" webkitallowfullscreen mozallowfullscreen allowfullscreen></iframe></div></p>
<p>more discussion about harmonic aliasing:</p>
<p><a href="https://forum.pdpatchrepo.info/topic/11176/adaptive-sample-rate-and-harmonic-aliasing-in-pd" rel="nofollow">https://forum.pdpatchrepo.info/topic/11176/adaptive-sample-rate-and-harmonic-aliasing-in-pd</a></p>
<p>.</p>
]]></description><link>http://forum.pdpatchrepo.info/topic/11176/adaptive-sample-rate-and-harmonic-aliasing-in-pd/3</link><guid isPermaLink="true">http://forum.pdpatchrepo.info/topic/11176/adaptive-sample-rate-and-harmonic-aliasing-in-pd/3</guid><dc:creator><![CDATA[lilakmonoke]]></dc:creator><pubDate>Fri, 19 Jan 2018 06:55:09 GMT</pubDate></item><item><title><![CDATA[Reply to adaptive sample rate and harmonic aliasing in PD? on Fri, 22 Dec 2017 00:16:59 GMT]]></title><description><![CDATA[<p>this is a video on a different topic but at one point he describes using windowed band limited impulses order to simulate other sample rates @ 20:52</p>
<p><div class="embed-container"><iframe src="//www.youtube.com/embed/lpM4Tawq-XU" width="640" height="360" frameborder="0" webkitallowfullscreen mozallowfullscreen allowfullscreen></iframe></div></p>
<p>you can obviously use a lowpass filter with samphold~ also..</p>
]]></description><link>http://forum.pdpatchrepo.info/topic/11176/adaptive-sample-rate-and-harmonic-aliasing-in-pd/4</link><guid isPermaLink="true">http://forum.pdpatchrepo.info/topic/11176/adaptive-sample-rate-and-harmonic-aliasing-in-pd/4</guid><dc:creator><![CDATA[seb-harmonik.ar]]></dc:creator><pubDate>Fri, 22 Dec 2017 00:16:59 GMT</pubDate></item><item><title><![CDATA[Reply to adaptive sample rate and harmonic aliasing in PD? on Fri, 22 Dec 2017 07:46:54 GMT]]></title><description><![CDATA[<p>really interesting this guy is from waldorf, who definitely know how to write brilliant audio code ... im not sure i would know how to do this in pd so id love to see an example patch.</p>
<p>ive just tried the approach by acreil and this works! its rather simple too, all you have to do is find a close integer relationship between the number of samples in your waveform, (128 in my case) and the frequency you want it to be played. ie. 8 : 5 x 128 and voila ALL DISHARMONIC ALIASING DISAPPEARS and turns into harmonic overtones, no matter how high the frequency is.</p>
<p>ill include a patch soon ...</p>
]]></description><link>http://forum.pdpatchrepo.info/topic/11176/adaptive-sample-rate-and-harmonic-aliasing-in-pd/5</link><guid isPermaLink="true">http://forum.pdpatchrepo.info/topic/11176/adaptive-sample-rate-and-harmonic-aliasing-in-pd/5</guid><dc:creator><![CDATA[lilakmonoke]]></dc:creator><pubDate>Fri, 22 Dec 2017 07:46:54 GMT</pubDate></item></channel></rss>