Audio Research Ref Phono 2SE owners - having hum problems with LOMC/Koetsu Any ideas?


Hello

Continuing to have a lot of ground loop like noise with Reference Phono 2SE using .2 MV output Koetsu into Spectral 30SV preamp and DMA-260.  Any ideas?  Feel like I have definitely isolated this to the phono stage as noise is not present on any of the other inputs.  

Note: Due to LOMC, I have to turn up volume to 2/3 for loud music playing and getting lots of hum when no signal is playing at that level.    Up to 1/2 volume, there is very little noise; tempted to move to higher output MC such as Lyra Titan, but Koetsu is near new, only 200 hours.  Have dedicated circuits, grounded together at the box, and disconnecting tonearm cable to phono preamp or taking turntable motor out of the system does not make any difference.

Please let me know of any suggestions or if this is the how the Ref 2SE is.

Thanks,

Carl
carl2001

Showing 1 response by swampwalker

KAB gain calculator says you only need 64 dB gain, your MC phono has 74 dB so insufficient gain should not be an issue. Assuming you have the cart feeding the MC input on the ARC, I don’t see why you need to have the volume set so high, unless you are in a BIG room with really inefficient speakers and like to listen at concert levels. Spectral components sometimes do not play nice with other gear, maybe that’s an issue. Agree that you should check w ARC.