[sdiy] NICs, GICs, NLOs and all that

[Osamu (Sam) HOSHUYAMA]

Hello Ian, Magnus, and List,

Ian Fritz wrote:
> It seems that there has not been much use of NICs and GICs (negative and
> generalized impedance converters) and related circuits in the synth-diy
> arena.  Recently JH reminded us that synthetic inductors constructed from
> classical gyrator circuitry may have important advantages in constructing
> fixed-frequency filter banks.  I've collected some interesting general
> information and circuit ideas in this area from the web and thought I would
> pass them along.  Of course, much of the basic information is also
> available in textbooks on network theory.

Orban uses gyrators in their products, not DIY though.  Their schematics
could be inspiring.

  Orban manuals (pdf):
           ftp://ftp.orban.com/

672 and 674 are parametric equalizers with unusual gyrators (NIC based).



FYI:
Other schematics are interesting as well.  However, most of the files 
are over 2 M bytes.  To choose the files to check, this short summary 
may be helpful.

   1xx: Reverberators
   2xx--3xx: Stereo synthesizers
   4xx: Compressors
   5xx: Sibilance controllers
   6xx: Equalizers
   8xxx--9xxx: Broadcasting systems

Especially, the followings are interesting for me:

   300: Stereo synthesizer  (2 pole fixed APFs are used)
   418: FET based compressor
   622: Parametric equalizer with unusual biquad filters
   642: Parametric equalizer with unusual filters
   672, 674: Equalizers with unusual gyrators


Best,
Sam Hoshuyama
-- - ---  - -- ------ - -------- -- - ---- -
Osamu (Sam) HOSHUYAMA      houshu at rogers.com
                              Ottawa, CANADA
--------------------------------------------