Cgs synth

Can someone confirm or deny this, re: questions on the CGS35 steiner
filter:

--For best audio performance, The 2N2222's connected to the 2K2
resistors (one base tied to LP, one base tied to Ground) should be
matched.

--The diodes in the ladder don't need to be matched.

--If I were to put attenuator pots on the LP, BP, HP inputs, I should
probably put a buffer (good quality op amp etc) between the pots and
input 47K resistors.

--To add additional CV mod sources, just hook more 220K resistors (or
whatever) to base of the leftmost 2N2222 and put the CV on the other
side.

Thanks in advance for the help....

>--For best audio performance, The 2N2222's connected to the 2K2
>resistors (one base tied to LP, one base tied to Ground) should be
>matched.

Probably. See below.

>--The diodes in the ladder don't need to be matched.

Technically matching would "help", but being a filter it probably wouldn't
be that noticable. - the difference in capacitors etc would probably out
weigh it.

>--If I were to put attenuator pots on the LP, BP, HP inputs, I should
>probably put a buffer (good quality op amp etc) between the pots and
>input 47K resistors.

No. Just use 50k pots directly.

>--To add additional CV mod sources, just hook more 220K resistors (or
>whatever) to base of the leftmost 2N2222 and put the CV on the other
>side.

Exactly.


Ken
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Ken Stone sasami@...
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