<HTML><FONT FACE=arial,helvetica><HTML><FONT SIZE=2 PTSIZE=10 FAMILY="SANSSERIF" FACE="Arial" LANG="0">In a message dated 7/19/2004 5:50:19 PM Eastern Standard Time, cfmd@bredband.net writes:<BR>
<BR>
<BLOCKQUOTE TYPE=CITE style="BORDER-LEFT: #0000ff 2px solid; MARGIN-LEFT: 5px; MARGIN-RIGHT: 0px; PADDING-LEFT: 5px">A state-variable filter is not built around low pass filters, it's built around<BR>
integrators. The standard (for synth cases) SVF is built from two integrators<BR>
and an input summer, you need the feedback paths to acheive the pole-pattern<BR>
control. The outputs of the summer and the integrators can then be summed to<BR>
form whatever zero-pattern you fancy.<BR>
</BLOCKQUOTE><BR>
The SVF is also equivalent to an analog computer circuit solving a general second-order differential equation with damping and an input forcing function. That's how I remember how to wire it up.<BR>
<BR>
Paul Camann<BR>
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