wow, you're talking about stuff i have not come across in my info search...can you explain this to me a little further? what exactly is "mod hum" or rectified mains equipment hum? can this be narrowed down to one piece of equipment? my fear is that it isn't "equipment" related as it doesn't seem to matter which combination of guitar/amp, vocal mic, etc...i can be using a completely different chain of equipment and still get similar results. would this be something "house" or "environment" related that might be affecting my gear?