a question about the MS-20 Sallen-Key LP VCF

[littlewing]

i'm wondering about the purpose of the two red LEDs in the Vr section of the following circuit:

http://www.geocities.com/tpe123/folkurb ... ppets.html

it seems as though they replace a second 100k resistor which would turn it into a voltage divider.

additionally, how would i go about replacing the pots with a vactrol, seeing as all three lugs on the pots are used?

thanks,
Vito

p.s. where is everybody? the board seems to have died lately.

[expanoncolin]

i'm wondering about the purpose of the two red LEDs in the Vr section of the following circuit:

http://www.geocities.com/tpe123/folkurb ... ppets.html

it seems as though they replace a second 100k resistor which would turn it into a voltage divider.

additionally, how would i go about replacing the pots with a vactrol, seeing as all three lugs on the pots are used?

thanks,
Vito

p.s. where is everybody? the board seems to have died lately.

The LEDs provide a voltage drop that works just like the resistor.  Just another method! The Freq pot is actually a CV so you don't need a vactrol there really.  Vactrolling resonance would be a bit harder.

I'm not sure - sometimes posts lapse.  Invite your friends!

-Colin

[littlewing]

aha, thanks colin, that cleared it all up. i can safely replace the LEDs with a 100k right?