Sota+SME IV=Ugh !!!

Hi Randy,

The arm was (and still is) a Magnepan Unitrac. I'm not completely certain as to whether or not the arm may have played a role in the hum, but my guess is that it did not.

Although it doesn't necessarily signify anything conclusive about the possible role of the arm, I'll mention fwiw that the hum completely disappeared when the arm was moved toward the rest position, as soon as the cartridge reached the point of not being directly over the rotating platter.

The only other thing I can add is that over the years I've heard a number of other reports of Grado's having hum problems with a few various non-SOTA turntables (I don't recall which ones), from those I know as well as well as on the web.

Best regards,
-- Al

I’m pursuing a Grado Reference for its characteristics and price point.

I would be cautious about the possibility of hum pickup, which the Grado's are prone to with SOME turntables, due to the lack of shielding that results from their wood construction. I used a Grado Sonata for a time with my SOTA Sapphire (from 1983 and still going strong!!), and there was a slight hum whenever the cartridge was moved into position above the rotating platter. By "slight" I mean that it was completely inaudible when music was playing, while being a little bit above the threshold of audibility at the listening position with no music playing and the volume control at typical settings.

Regards,
-- Al

03-02-12: Stringreen
The hum that the above poster is talking about comes from the Grado cartridge. They don't do well with some arms. Even if the hum is inaudible when playing music, it depletes the amp from valuable power and lessons the quality of the audio.

While I would not completely rule out the possibility of adverse effects on audio quality, if there were any such effects it would not be because of power depletion. For typical speaker efficiencies the hum levels we are discussing probably correspond to less than a thousandth of a watt.

Regards,
-- Al