[sdiy] moog high pass flter

[Osamu (Sam) HOSHUYAMA]

Hello List,

Happy New Year!

I put a new schematic to explain my idea to implement HPF input into 
the vertical ladder filter.

   http://www5b.biglobe.ne.jp/~houshu/synth/index.html

Vcfv0212.GIF is the schematic.

Enjoy,

Sam Hoshuyama

"Osamu (Sam) HOSHUYAMA" wrote:
> To minimize the influence on the pole of the top stage, the capacitors
> to inject the HPF input should be twice as much as those of the other 
> stages, and the amplifiers (attenuators) to generate balanced signals 
> should have very low output impedance compared with the impedance of 
> the capacitors.
> 
> Actually, the attenuators can be implemented with capacitors not
> resistors.  By using this technique, we'll be able to build transistor-
> ladder Sallen-Key filters.  If I have time in the coming holidays, 
> I'd draw some schematics to explain the ideas.

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