<html><head><meta http-equiv="Content-Type" content="text/html; charset=windows-1252"></head><body><div><div style="font-family: Calibri,sans-serif; font-size: 11pt;">Hi<br><br>Im looking at schematics to try and add a HPF knob to a Yamaha SY1. Its all nice and easy: the HPF cutoff input on the PCB takes 0-10v (so adding a socket would be trivial) and there are a few PCB points that provide a 10v source.<br><br>Question: to add a knob to control the HPF cutoff, is it simply a case of using an appropriate variable resistor: 10v -> VR -> HPF? Would this VR then sweep the 10v input from 0v to 10v output? Im guessing it might not be this simple :(<br><br>Any pointers will be very appreciated..<br><br>Thanks,<br><br>Paul<br>London<br>www.punkdisco.co.uk</div></div></body></html>