Hi Ack,
For fun I re-read your orgin. post and I have to nod my head re: the R>L channel hum. I get a persistant ground (?) hum that is greater in the right channel. I have had this forever. What's interesting is that like you mention, if I unhook the tonearm cable from the phono preamp, this hum goes away. It is not evident in my digital set up at all. Boy, if only the analog output was a quiet as my digital (no source playing) I'd be an ecstatic vinylphile. Lately, I have been really playing around with trying to get my LP-S to sound how I want it and have been tube rolling and switching btwn two phono cables. It's interesting that my one cable, of which I have three, ( 2 of the same version one of a another version) all give R>L channel hum. Yet, my other cable from diff. manuf., is quieter and does not accentuate a right channel hum, but allows EM/RF "pops" from nearby kitchen appliances to enter the chain.
Recently I've found out (again) that touching the tonearm anywhere causes a mild hum. This I remember from before but forgot about and as far as I can determine is the direct result of the outside street powerline RF that plagues my system. I also assume that my low level ground hum in the analog chain is also related to the street powerlines. I have been unsuccessful in my many attempts to get rid of the effect w/o success. Short of moving my system to another room, maybe someday, I have little confidence I will ever rid my system of it. But, the little tool mentioned for meas. current may be a new start!!
For fun I re-read your orgin. post and I have to nod my head re: the R>L channel hum. I get a persistant ground (?) hum that is greater in the right channel. I have had this forever. What's interesting is that like you mention, if I unhook the tonearm cable from the phono preamp, this hum goes away. It is not evident in my digital set up at all. Boy, if only the analog output was a quiet as my digital (no source playing) I'd be an ecstatic vinylphile. Lately, I have been really playing around with trying to get my LP-S to sound how I want it and have been tube rolling and switching btwn two phono cables. It's interesting that my one cable, of which I have three, ( 2 of the same version one of a another version) all give R>L channel hum. Yet, my other cable from diff. manuf., is quieter and does not accentuate a right channel hum, but allows EM/RF "pops" from nearby kitchen appliances to enter the chain.
Recently I've found out (again) that touching the tonearm anywhere causes a mild hum. This I remember from before but forgot about and as far as I can determine is the direct result of the outside street powerline RF that plagues my system. I also assume that my low level ground hum in the analog chain is also related to the street powerlines. I have been unsuccessful in my many attempts to get rid of the effect w/o success. Short of moving my system to another room, maybe someday, I have little confidence I will ever rid my system of it. But, the little tool mentioned for meas. current may be a new start!!