SME 20/2 Finger Lift Hum

Your body is creating some sort of ground loop. If this is really an issue, you could cover the finger lift with some heat shrink tubing, or any other form of insulation. But be aware that this will increase tonearm effective mass. Otherwise, the obvious retort is "don't touch the finger lift while LPs are in play". Why would you ever want to do that?

IMO, if there were an overall issue with grounding the tonearm (i.e., if there were a potential difference between his tonearm and his phono stage, for example), the hum would be audible at all times, whether or not the OP touched the finger-lift.

Hi Larry, That's what I originally suggested - insulate the arm lift OR don't touch it. If the system is elevated from true ground for some reason, for example due to a faulty wall socket, it is conceivable to me that one's body could be at a lower potential. When you contact the arm, only then is there a loop. There are several variations on this theme, but I hope you get my idea. The body as antenna usually results in a higher pitched noise, not true hum.

Also, if the tonearm is grounded to the phono stage, as someone else suggested, it might be of interest to un-ground it. If we then don't have hum, my hypothesis is supported. Anyway, changing the current grounding scheme, whatever it is, might reduce or enhance the problem, and that information would be valuable.

Unless I have completely misunderstood what is going on here (and that is entirely possible), I don't quite understand why you are so exercised over it. If insulating the lift has cured the problem, I especially do not get it. I would think of that as a "permanent solution" and go on from there to enjoy the music.

For example, my dedicated MM phono stage will put a low level buzz on my speakers, if I don't dress the umbilical cord from its power supply so as to be clear of the AC cord. So I taped it up to stay away from the AC cord. I consider that "case closed", but the reality is not unlike the one you describe; I used a bandaid to fix a problem. So what?

Dear Dover, If you re-read the thread you will see that every single point you made has already been made, and your "theory" has already been proposed. At least you and I and others agree. Insulating the finger-lift has apparently worked to eliminate the hum; the OP is not totally happy, however.