[sdiy] understanding the CAP arrangement on the PT2399 (filters)

[Dan Snazelle]

looking at

http://sites.google.com/site/hearnmorley/synth-diy-resources/GHSYN2bWeb.pdf?attredirects=0

or even at the PT2399 datasheet, i have never understood the signal flow in the "internal opamps"

to me it looks like the input is connecting VIA r5 to the first opamp which has a 1n in its feedback loop. but is r6 connecting into the next opamp or into the feedback loop of the first one? and there is similar confusion on following the path (and determining the cutoffs) on the additional internal opamps

thanks for any help