[sdiy] vco-vcf CV tracking

[Gavin Russom]

Okay, 
If I am using a patch where the same CV is controlling a VCO and the VCF
that is filtering it, then I should get this result:  as the CV changes I
would hear the pitch change but each pitch would be filtered in the same
way, if filter cuttoff was selected to produce a hollow reedy sound then
each pitch would have a hollow reedy sound, right?
What shouldn't happen is that the changing pitch goes in and out of
audibility because it is being filtered in different ways, right?
Standard modular procedure is to use 100k input impedence, which was
followed in this case, but when I use a sequencer to control my homebuilt
VCO and VCF in this manner, they do not track properly.  What would need to
be adjusted in this case?  Perhaps a trim pot for the 1V/oct inputs? 
Temperature compensation?
Glad to hear all ideas
Thanks again
Gavin