Help/UGens/Filters/FreqShift.html

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  27 <p class="p1"><b>FreqShift<span class="Apple-tab-span"> </span><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span>Frequency Shifter</b></p>
  28 <p class="p1">add</p>
  29 <p class="p2"><b>FreqShift.ar(input, shift, phase, mul, add)</b></p>
  30 <p class="p3"><br></p>
  31 <p class="p2">FreqShift implements single sideband amplitude modulation, also known as frequency shifting, but not to be confused with pitch shifting.<span class="Apple-converted-space">  </span>Frequency shifting moves all the components of a signal by a fixed amount but does not preserve the original harmonic relationships.</p>
  32 <p class="p3"><br></p>
  33 <p class="p2"><b>input</b> - audio input</p>
  34 <p class="p2"><b>shift</b> - amount of shift in cycles per second</p>
  35 <p class="p2"><b>phase </b>- phase of the frequency shift (0 - 2pi)<b><span class="Apple-converted-space"> </span></b></p>
  36 <p class="p3"><br></p>
  37 <p class="p3"><br></p>
  38 <p class="p2"><b>Examples</b></p>
  39 <p class="p3"><br></p>
  40 <p class="p4">// shifting a 100Hz tone by 1 Hz rising to 500Hz</p>
  41 <p class="p5">{<span class="s1">FreqShift</span>.ar(<span class="s1">SinOsc</span>.ar(100),<span class="s1">XLine</span>.kr(1,500,5),0,[0.5,0.5])}.play(s);</p>
  42 <p class="p6"><br></p>
  43 <p class="p4">// shifting a complex tone by 1 Hz rising to 500Hz</p>
  44 <p class="p5">{<span class="s1">FreqShift</span>.ar(<span class="s1">Klang</span>.ar(`[[101,303,606,808]]),<span class="s1">XLine</span>.kr(1,500,10),0,[0.25,0.25])}.play(s);</p>
  45 <p class="p6"><br></p>
  46 <p class="p4">// modulating shift and phase</p>
  47 <p class="p5">{<span class="s1">FreqShift</span>.ar(<span class="s1">SinOsc</span>.ar(10),<span class="s1">LFNoise2</span>.ar(0.3,1500),<span class="s1">SinOsc</span>.ar(500).range(0,2pi),[0.5,0.5])}.play(s);</p>
  48 <p class="p6"><br></p>
  49 <p class="p4">// the ubiquitous houston example</p>
  50 <p class="p5">(</p>
  51 <p class="p7"><span class="s2">b = </span><span class="s1">Buffer</span><span class="s2">.read(s,</span>"sounds/a11wlk01.wav"<span class="s2">);</span></p>
  52 <p class="p5">{<span class="s1">FreqShift</span>.ar(<span class="s1">PlayBuf</span>.ar(1,b,<span class="s1">BufRateScale</span>.kr(b),loop:1),<span class="s1">LFNoise0</span>.kr(0.45,1000),0,[1,1])}.play(s);</p>
  53 <p class="p5">)</p>
  54 <p class="p6"><br></p>
  55 <p class="p4">// shifting bandpassed noise</p>
  56 <p class="p5">{<span class="s1">FreqShift</span>.ar(<span class="s1">BPF</span>.ar(<span class="s1">WhiteNoise</span>.ar(1),1000,0.001),<span class="s1">LFNoise0</span>.kr(5.5,1000),0,[32,32])}.play(s);</p>
  57 <p class="p3"><br></p>
  58 <p class="p3"><br></p>
  59 <p class="p2"><b>More Examples </b>(send a SynthDef, run the routine then send a different SynthDef)</p>
  60 <p class="p3"><br></p>
  61 <p class="p4"><span class="s2">(</span>// simple detune &amp; pitchmod via FreqShift</p>
  62 <p class="p5"><span class="s1">SynthDef</span>(<span class="s3">"frqShift1"</span>,{<span class="s1">arg</span> frq,detune=1.5;</p>
  63 <p class="p5"><span class="Apple-tab-span">     </span><span class="s1">var</span> e1,left,right;<span class="Apple-tab-span">  </span></p>
  64 <p class="p5"><span class="Apple-tab-span">     </span>e1 = <span class="s1">EnvGen</span>.ar(<span class="s1">Env</span>.new([0,1,0],[1,2.3]),1,doneAction:2);</p>
  65 <p class="p5"><span class="Apple-tab-span">     </span>left = <span class="s1">SinOsc</span>.ar(frq,0,e1); <span class="s4">// original tone</span></p>
  66 <p class="p5"><span class="Apple-tab-span">     </span>left = left + <span class="s1">FreqShift</span>.ar(left,frq*detune); <span class="s4">// shift and add back to original<span class="Apple-converted-space"> </span></span></p>
  67 <p class="p5"><span class="Apple-tab-span">     </span>right = <span class="s1">FreqShift</span>.ar(left,<span class="s1">SinOsc</span>.kr(3.23,0,5));</p>
  68 <p class="p5"><span class="Apple-tab-span">     </span><span class="s1">Out</span>.ar(0, [left,right] * 0.25);</p>
  69 <p class="p5">}).add;</p>
  70 <p class="p5">)</p>
  71 <p class="p3"><br></p>
  72 <p class="p4"><span class="s2">(</span>// the routine</p>
  73 <p class="p8"><span class="s2">r = </span>Routine<span class="s2">({</span></p>
  74 <p class="p5"><span class="Apple-tab-span">     </span><span class="s1">var</span> table,pitch;</p>
  75 <p class="p5"><span class="Apple-tab-span">     </span>table = [0,2,4,5,7,9,11,12];</p>
  76 <p class="p5"><span class="Apple-tab-span">     </span><span class="s1">inf</span>.do{</p>
  77 <p class="p5"><span class="Apple-tab-span">     </span><span class="Apple-tab-span">    </span>pitch = (48+(12*2.rand) + table.choose).midicps;</p>
  78 <p class="p5"><span class="Apple-tab-span">     </span><span class="Apple-tab-span">    </span>s.sendMsg(<span class="s3">"s_new"</span>,<span class="s3">"frqShift1"</span>,-1,1,1,<span class="s3">"frq"</span>,pitch);</p>
  79 <p class="p5"><span class="Apple-tab-span">     </span><span class="Apple-tab-span">    </span>3.wait;</p>
  80 <p class="p5"><span class="Apple-tab-span">     </span><span class="Apple-tab-span">    </span>};</p>
  81 <p class="p5"><span class="Apple-tab-span">     </span>};</p>
  82 <p class="p5">).play;</p>
  83 <p class="p5">)</p>
  84 <p class="p6"><br></p>
  85 <p class="p4"><span class="s2">(</span>// shift pulse wave in opposite directions</p>
  86 <p class="p5"><span class="s1">SynthDef</span>(<span class="s3">"frqShift1"</span>,{<span class="s1">arg</span> frq,detune=0.15;</p>
  87 <p class="p5"><span class="Apple-tab-span">     </span><span class="s1">var</span> e1,snd,left,right;<span class="Apple-tab-span">      </span></p>
  88 <p class="p5"><span class="Apple-tab-span">     </span>e1 = <span class="s1">EnvGen</span>.ar(<span class="s1">Env</span>.new([0,1,0],[0.02,3.2]),1,doneAction:2);</p>
  89 <p class="p5"><span class="Apple-tab-span">     </span>snd = <span class="s1">Pulse</span>.ar(frq,<span class="s1">SinOsc</span>.kr(2.3).range(0.2,0.8),e1); <span class="s4">// original tone</span></p>
  90 <p class="p5"><span class="Apple-tab-span">     </span>left = <span class="s1">FreqShift</span>.ar(snd,<span class="s1">XLine</span>.kr(-0.1,-200,2)); <span class="s4">// shift and add back to original<span class="Apple-converted-space"> </span></span></p>
  91 <p class="p5"><span class="Apple-tab-span">     </span>right = <span class="s1">FreqShift</span>.ar(snd,<span class="s1">XLine</span>.kr(0.1,200,2));</p>
  92 <p class="p5"><span class="Apple-tab-span">     </span><span class="s1">Out</span>.ar(0, [left,right] * 0.25);</p>
  93 <p class="p5">}).add</p>
  94 <p class="p5">)</p>
  95 <p class="p6"><br></p>
  96 <p class="p4"><span class="s2">(</span>// FreqShift &gt;&gt; feedback &gt;&gt;&gt; FreqShift</p>
  97 <p class="p7"><span class="s1">SynthDef</span><span class="s2">(</span>"frqShift1"<span class="s2">,{</span><span class="s1">arg</span><span class="s2"> frq;</span></p>
  98 <p class="p5"><span class="Apple-tab-span">     </span><span class="s1">var</span> e1,snd,snd2,in;</p>
  99 <p class="p5"><span class="Apple-tab-span">     </span>in = <span class="s1">FreqShift</span>.ar(<span class="s1">InFeedback</span>.ar(0,1)*3.2,<span class="s1">XLine</span>.ar(0.01,frq*1.5,1)); <span class="s4">// shift the feedback</span></p>
 100 <p class="p5"><span class="Apple-tab-span">     </span>e1 = <span class="s1">Env</span>.new([0,1,0],[0.02,2.98]);</p>
 101 <p class="p5"><span class="Apple-tab-span">     </span>snd = <span class="s1">SinOsc</span>.ar(frq,0,<span class="s1">EnvGen</span>.ar(e1,1,doneAction:2));</p>
 102 <p class="p5"><span class="Apple-tab-span">     </span>snd2 = <span class="s1">FreqShift</span>.ar(snd+in,<span class="s1">SinOsc</span>.ar(4.24,0.5,3),0,0.5); <span class="s4">// subtle modulating shift</span></p>
 103 <p class="p5"><span class="Apple-tab-span">     </span><span class="s1">OffsetOut</span>.ar([0,1], <span class="s1">Limiter</span>.ar(snd2+snd * 0.5,1,0.005));</p>
 104 <p class="p5">}).add;</p>
 105 <p class="p5">)</p>
 106 <p class="p6"><br></p>
 107 <p class="p4"><span class="s2">r.stop; </span>// stop old routine</p>
 108 <p class="p6"><br></p>
 109 <p class="p4"><span class="s2">(</span>// ssllooww columbia tuned shift detune</p>
 110 <p class="p9"><br></p>
 111 <p class="p7"><span class="s1">b = Buffer</span><span class="s2">.read(s,</span>"sounds/a11wlk01.wav"<span class="s2">);</span></p>
 112 <p class="p6"><br></p>
 113 <p class="p5"><span class="s1">SynthDef</span>(<span class="s3">"frqShift1"</span>,{<span class="s1">arg</span> frq, bufnum;</p>
 114 <p class="p5"><span class="Apple-tab-span">     </span><span class="s1">var</span> e1,snd,left,right;</p>
 115 <p class="p5"><span class="Apple-tab-span">     </span>e1 = <span class="s1">Env</span>.new([0,1,0],[3,1],-4);</p>
 116 <p class="p5"><span class="Apple-tab-span">     </span>snd = <span class="s1">PlayBuf</span>.ar(1, bufnum, <span class="s1">BufRateScale</span>.kr(bufnum) * 0.01, loop:1);</p>
 117 <p class="p5"><span class="Apple-tab-span">     </span>left = <span class="s1">FreqShift</span>.ar(snd,frq*2,0,<span class="s1">EnvGen</span>.ar(e1,1,doneAction:2)); <span class="s4">// subtle shift of the output</span></p>
 118 <p class="p5"><span class="Apple-tab-span">     </span>right = <span class="s1">FreqShift</span>.ar(snd,frq*3,0,<span class="s1">EnvGen</span>.ar(e1,1,doneAction:2));</p>
 119 <p class="p5"><span class="Apple-tab-span">     </span><span class="s1">Out</span>.ar(0, [left,right] * 3);</p>
 120 <p class="p5">}).add;</p>
 121 <p class="p4"><span class="s2">(</span>// the routine</p>
 122 <p class="p8"><span class="s2">r = </span>Routine<span class="s2">({</span></p>
 123 <p class="p5"><span class="Apple-tab-span">     </span><span class="s1">var</span> table,pitch;</p>
 124 <p class="p5"><span class="Apple-tab-span">     </span>table = [0,2,4,5,7,9,11,12];</p>
 125 <p class="p5"><span class="Apple-tab-span">     </span><span class="s1">inf</span>.do{</p>
 126 <p class="p5"><span class="Apple-tab-span">     </span><span class="Apple-tab-span">    </span>pitch = (48+(12*2.rand) + table.choose).midicps;</p>
 127 <p class="p5"><span class="Apple-tab-span">     </span><span class="Apple-tab-span">    </span>s.sendMsg(<span class="s3">"s_new"</span>,<span class="s3">"frqShift1"</span>,-1,1,1, <span class="s3">"frq"</span>, pitch, <span class="s3">"bufnum"</span>, b);</p>
 128 <p class="p5"><span class="Apple-tab-span">     </span><span class="Apple-tab-span">    </span>3.wait;</p>
 129 <p class="p5"><span class="Apple-tab-span">     </span><span class="Apple-tab-span">    </span>};</p>
 130 <p class="p5"><span class="Apple-tab-span">     </span>};</p>
 131 <p class="p5">).play;</p>
 132 <p class="p5">)</p>
 133 <p class="p6"><br></p>
 134 <p class="p5">)</p>
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