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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I’m having some trouble getting the Envelope Shapers
to work properly in the Minisonic2 I’m making. If interested, you can
find the gory details in a new section on my Minisonic2 web page: <a
href="http://pcbunn.cacr.caltech.edu/jjb/Synthesizers/Minisonic2/">http://pcbunn.cacr.caltech.edu/jjb/Synthesizers/Minisonic2/</a>
(In fact I would welcome suggestions on what may be wrong, if you are so
inclined).<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>As a sanity check I downloaded a freeware Spice program and used
it to simulate the Envelope Shaper circuit, which of course behaved exactly as
it should do (sensible rise/decay times) and not as I was measuring with the
scope on my board. <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>The next thing I’m going to simulate for fun is the
VCF’s ladder network.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>It occurred to me that, given the circuit diagrams for e.g.
a Moog, and a lot of free time, one could enter everything into Spice and
completely simulate the behaviour of the instrument. With the results you could
make a faithful digital reproduction of the Moog. And you’d never need to
touch a soldering iron </span></font><font size=2 face=Wingdings><span
style='font-size:10.0pt;font-family:Wingdings'>J</span></font><font size=2
face=Arial><span style='font-size:10.0pt;font-family:Arial'><o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I’m wondering whether anyone has done this, for a Moog
or any other type of analogue synth.?<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Julian<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>PS Perhaps simulating some of the obsolete semiconductors
would be the tricky part.<o:p></o:p></span></font></p>
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