PLAN B analog blog

From Peter Grenader:

There are two things you need to check:

1) is the amplitude of the two signals you are inputting iinto INJECT A and B equal in amplitude to begin with?

2) You need to adjust the trim pot on the second board - this effects the linearity of the cross fade . There is only one trimmer on that assembly - it's easy to find.

As far as the cross fade VC, like a VCA it does not accept bipolar control signals - only positive voltages and because of this  it can only move from one direction so yes, you need to offest the manual pot to acheive the xfade amount you need.

Jari's original post:

Yesterday I did some cross fading with M14. I used inject_a and 
inject_b inputs and got smooth cross fading both with xfade knob and 
vc_xfade input.

However, it is strange, that the xfade knob has to be set slightly over 
9 o'clock to get equal balance between inject_a and inject_b. This is, 
when no voltage is applied to the vc_xfade input. One would assume to 
get equal balance at 12 o'clock.

Furthermore, when I apply bipolar LFO sine into the vc_xfade, I have to 
readjust: To get "symmetrical" cross fade between inject_a only and 
inject_b only, the xfade knob has to be (carefully) set slightly under 
9 o'clock.

This is inconvenient in my opinion. It reminds the bandwidth/cross-fade 
knob of my M12, about which I complained earlier: Too much sensitivity 
near full counter clockwise position.

Best regards
Jari Jokinen