[sdiy] Good 24db/oct HP-LP-BP-Notch filter Schematics ??

[Neil Johnson]

Mattias Rickardsson wrote:
> Is the schematic of your 3-pole SVF available perhaps, as a
> comparison? The link is broken. :-)
> http://www.milton.arachsys.com/nj71/index.php?menu=2&submenu=0&subsubmenu=1

Yes the link is broken.  If anyone wants a copy they can ask, but
following the suspected actions of a certain company I won't be
providing schematics online of anything I might one day want to
release as a commercial product.

But yes, a 3-pole SVF extends the 2-pole form, adding a third pole
which sits on the real axis.  Adding a fourth integrator adds one more
pole, so giving two conjugate pole-pairs.  It is the damping that gets
"interesting".

Neil
--
http://www.njohnson.co.uk