Nulling process?

[w!ll]

I've been working on this ring modulator (with a true bypass set-up) for a while..

Using the nulling set-up from this one..


I was wondering if anyone could outline a step by step nulling process? The signal null does a pretty good job of getting rid of oscillator bleed, but i'm not sure what the carrier null is supposed to do or how to set it up? It doesn't seem to have any effect on the sound. At the moment i'm getting a lot of buzz/fuzz type sounds when the mix is on full, i'm getting the feeling this is perhaps due to not carrying out the nulling process properly? or maybe something else? I'm using a +/-15v PS and some multi-turn trimpots for the nulling. Any help would be greatly appreciated.

Will.