Preamp Deal of the Century

Query re sauvignon linestage

I have had a sauvignon linestage for 2 years plus. It has always had an annoying hum in the left channel only. I have definitely isolated it to the preamp. It becomes almost non audible when the gain is turned down, but this also results in a loss of dynamics. I had the preamp checked out by a local valve guru and he couldn't find anything wrong. Another interesting thing is that when the remote is used, a higher frequecy humm comes from the left speaker only. I assume this is motor noise from the volume control motor?? The right channel is dead quiet. I have rolled the tubes. Currently using NOS Tung Sol's which IMHO are light years ahead of the EH stock tubes. Only yesterday I tried out a RAL umbilical cord but I think it has made the sound less musical. It is shorter than Mick's cord and the left channel hum is definitely louder. I suspect the hum is power supply related. The RAL cord is shorter than Mick's. I'm almost at the point of giving up with the Suavignon but I haven't heard anything that sounds remotely as good.

Any ideas appreciated.
Thanks Mark.

mark:

i'd suggest you email mick and see if you can't ship the sauvignon to either him or kevin covi (depending on your location) for repair. i know you stated that you had the preamp checked out, but i would tend to believe that mick or kevin could find the problem if it is indeed in the preamp as you suspect.

I spoke to Mick today and he thinks it might be picking up some ac current from a nearby transformer. I followed his suggestion and moved it well away from any power source, but still the same. Possible a faulty output transformer?? I have subsequently emailed him. Here's hoping.

I had the some problem hum in right channel. Changed tubes, moved speakers, always in right channel. I did not have that problem in previous apartment, Supratek was dead quiet. But since I have moved, hum is constant.
It is mains, power cables related. Recently I have bought umbilical cord from Brat. I was really angry that it took him so long. But to be honest hum is gone first in 2 years. I still cannot believe it. Neither power cables not interconnects did that much of a difference for me. Dynamic is better, micro dynamic is better too. I doubt that in previous place they would be such a difference but for peoples with hum problem it is a great buy.

I have also got a RAL umbilical lead but it makes no differene to the hum. I am certain it is related to the power supply somehow but I still haven't worked it out.