Cgs synth

>
>hi all,
>starting n a dual psycho lfo panel.
>I was think of a simple comparator output in addition to the normal
>outputs.
>This extra out would come from a comparator, comparing
>each p-lfo before the glide circuit. not sure how much design I need,
>I was thinking a dual op-amp (tl072) with 1 k inputs resistors from
>thelfo tap followed by a second op-amp as a buffer with 1 k output.

Go up to 10k input resistors - less stress on the op-amp inputs.

>no sure what the "high" level will be from the comparator, but
>whatever the voltage the follower could make it +5 ....

As the op-amp will be across the +/- power rails, the output will swing
between + and -, almost reaching the power rail. If you want 5V out, connect
a 1N4148 to the output of the opamp (anode to the output). Connect a 1k8
from the cathode of the diode to the output jack. Connect a 1k from the
output jack to GND

Ken
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Ken Stone sasami@...
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