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    <p>I think a few have cropped up recently in Euro (but I can't think
      of names)<br>
      If the VCF is based around an OTA then it is often fairly easy to
      add linear to the usual sort of matched-pair exponential converter
      - not sure how that'd help with temperature compensation though.<br>
      Somehow I don't think I ever actually tried it though.<br>
    </p>
    <br>
    <div class="moz-cite-prefix">On 09/11/2018 16:53, Mattias
      Rickardsson wrote:<br>
    </div>
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cite="mid:CAP92RBWEeFNwtVpn7aqjz01b00eLvb-ZbVF+Bacs=uubTNrAQw@mail.gmail.com">
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          <div dir="ltr">Hi all,</div>
          <div dir="ltr"><br>
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          <div dir="ltr">following the recent discussions about
            temperature compensation of exponentially VCFs, one could
            imagine that the easiest way of avoiding the temperature
            dependence would be to control the filter linearly (Hz/V)
            instead of exponentially. I can't remember seeing it done in
            a VCF, though. Even if there are VCOs with linear control in
            currently produced synths - the latest example might be the
            Moog One if I'm correctly informed.</div>
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          </div>
          <div>A quick search in the SDIY archives returned some hits in
            an interesting old thread called "Filter frequency cutoff
            with linear response?" from 2012, where Olivier Gillet,
            Florian Anwander and <span
              style="color:rgb(0,0,0);font-family:arial">Tom Wiltshire
              pointed out that the CEM3394 has linear filter FM from the
              onboard VCO's triangle wave via an onboard modulation VCA.
              The datasheet of the CEM3394 describes it some more. I
              remember liking the filter FM in the Akai AX-60, and this
              was it. </span><span
              style="color:rgb(0,0,0);font-family:arial">It still relies
              on exponential VCF in the regular filter CV input though.</span></div>
          <div><span style="color:rgb(0,0,0);font-family:arial"><br>
            </span></div>
          <div><span style="color:rgb(0,0,0);font-family:arial">PAiA
              Fatman was mentioned as having linear control of both VCO
              and VCF. Any other pure Hz/V filters out there? Or do
              people consider it a genuinly bad idea (except for the
              lack of V/oct CV input and the need of increased CV
              resolution/precision in the lower frequency range)? The
              bonus possibilities of linear FM might make it worthwhile.
              :-)</span></div>
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            <div>/mr</div>
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</pre>
    </blockquote>
    <br>
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